By MICHAEL WINES

        The freedom from State survelliance is being supplanted by a resurgent government obsession with internal security and threats from abroad — a phenomenon that they say has set off a limited but growing crackdown on supposed challenges to the state.

The evidence itself is scattered. It ranges from a string of arrests of Russian scholars, to the revival of old curbs on international scientific cooperation, to the seeming harassment of some political critics and dissidents, to a growing conviction among some intellectuals that their telephones are again being tapped and their e-mail read.

"It has not yet acquired the scope which would go deep under the skin of ordinary Russians. They have known much worse," Georgi Arbatov, the director emeritus of the government's Institute of U.S.A.-Canada Studies and a veteran analyst of East-West relations, said in an interview. "But there are some not very good signs.

"Having become the leader of this country, he has to explain that he does not want to return to some past practices. The sooner he dispels all these rumors, the better."

Never far from the surface of these concerns, of course, is the memory of Russia's seven decades as a rigid and ruthless police state. Virtually no one believes that a return to those days is either contemplated or even possible; whatever the flaws in Russia's justice system and its press, most Russians, though not all, enjoy basic civil liberties.

The Kremlin proposed judicial reforms this month that should underpin those liberties if carried out.

But Mr. Putin himself has rung alarm bells by suggesting that Russia requires what he calls a "managed democracy" headed by a strong central government. Over the Kremlin's insistence that it is irrevocably dedicated to basic freedoms, some liberals here call that a euphemism for authoritarian rule.

Top government posts have increasingly been filled by veterans of the military and intelligence, agencies that clung to a cold-war notion of security even in Russian democracy's most liberal days.

Many liberals question whether those and other officials, often steeped for decades in the Soviet bureaucracy before making quick changes in ideologies and jobs, have put the paranoia and xenophobia of Communist days behind them.

"They do just what they have been taught to do," said Sergei Kovalyov, a dissident who survived imprisonment in the infamous Perm-36 gulag in Siberia and is now in Parliament. "It's the only thing they can do. And that's why there is nothing surprising in the way they understand order in this country and what kind of order they are going to bring."

In the eyes of Mr. Kovalyov and other activists, a flurry of events in the last year are evocative of a dormant era when all outsiders were viewed as potential enemies — and challenging the established order could easily make one an outsider.

Some of those events, like the military's insistence that the nuclear submarine Kursk was probably sunk 10 months ago by a collision with a foreign sub spying on naval war games, amount to little more than words. Others have more serious consequences.

Only today the Federal Security Service's Omsk regional office announced that it had reprimanded Elizabeth Sweet, an American lecturer at the State University of Omsk, after counterintelligence officers learned that she had asked students to examine the economic health of local businesses. Most of the region's industry is military-related.

The security service said that such information could harm the image and competitiveness of businesses if published abroad, but it stopped short of expelling Ms. Sweet. It said, though, that the renewal of her teaching contract was now in doubt.

In Kaluga, 85 miles west of Moscow, Igor Sutyagin, a Russian military analyst at the Institute of U.S.A.- Canada Studies, Mr. Arbatov's old agency, is on trial for high treason, accused of passing state secrets.

International scientific organizations and Mr. Sutyagin's colleagues call the proceeding a sham, noting that he had no access to classified information. The charges appear based on his acceptance of a contract with a London consulting firm to write military analyses.

In Krasnoyarsk, in southern Siberia, a university scientist was charged with high treason in April for fulfilling a contract with a Chinese company to supply research on shielding satellites from radiation. His colleagues said the information was based on documents declassified 10 years ago.

In Vladivostok, a military court is beginning a second trial of Grigory Pasko, a military journalist accused of treason after helping Japanese television journalists report on the Russian naval fleet's dumping of nuclear waste at sea. Mr. Pasko was acquitted on the same charge in 1999; the Supreme Military Collegium ordered a retrial this year.

Civil rights advocates disclosed last week that the Russian Academy of Sciences had ordered scientists and their supervisors to restrict contacts with outsiders, report on trips abroad and submit potentially sensitive scientific papers for prepublication review, among other curbs.

The academy has not commented on the rules, some of which are said to apply only to classified scientific work and others to all scientists. Privately, civil liberties advocates here say similar restrictions have been put in place in other government agencies that have regular contact with foreigners.

Right or wrong, many intellectuals and activists now take it as a given that their telephone conversations and e-mail are monitored — something that, while surely not unthinkable, was hardly a major concern even two or three years ago.

Since 1995, Russian law has required all telephone and Internet services to maintain devices that allow the Federal Security Service, the post-Soviet evolution of the K.G.B., to monitor any and all transmissions. The service is required to seek a warrant before conducting a wiretap, but because it wields almost complete control over the process, it is not known how rigidly that requirement is followed.

The United States government has recently advised certain private entities that maintain regular contact with Russian officials, academics or businesses to assume that the Russians are monitoring all conversations.

Leaders of Yabloko, one of the political parties that promote Western-style democratic values, worried at a meeting in St. Petersburg on Saturday that Russia was becoming a society with the trappings of freedom, but controlled in reality from the top.

The Union of Right Forces, the other major liberal party, has publicly expressed concern of late that Russia could become a liberal economic state controlled by an authoritarian leadership.

Still, many in Russia's democratic elite are reluctant to tie the resurgence of suspicion and security measures directly to Mr. Putin, a former K.G.B. agent who was director of the Federal Security Service not six months before becoming president.

The more benevolent view is that his ascension has been read by Russia's security organs as a green light to return to old habits — or that the crackdown is a ham-handed attempt by midlevel bureaucrats to curry favor with the new president.

"During the 90's they were on the periphery of the establishment," said Igor Bunin, the head of Moscow's nonpartisan Center for Political Technologies. "Suddenly, they were all taken inside, right into the core of it. And they all decided that they have to prove that they are in demand, that they are needed by the state."

What is very likely under way, Mr. Bunin said, is a spate of muscle- flexing by the old crowd that has returned to control in some of the most powerful cabinet agencies.

"It also must be admitted that nobody has tried to cool them down and tell them they shouldn't be too zealous about it," he added.

That troubles many democratic and civil-rights advocates most of all. Many, though hardly all, of the best-known incidents involve the Federal Security Service — the closest modern equivalent to the domestic arm of the K.G.B. that once weeded dissenters and wrong-thinkers out of Soviet society and into gulags.

By not speaking out, they say, Mr. Putin has tacitly endorsed actions that seem devised to send a public message that there are limits to challenging the state and to consorting with the potential enemy.

"Some people are concerned," Mr. Arbatov said. "And it's not good. I think with the history we have, you cannot play games with such issues."

One who knows that history well is Sergei Grigoryants, another prominent dissident, who spent 10 years in Soviet prison camps in the 1970's and 1980's and who has been a fierce critic of the reluctant way that Russia has introduced democracy.

On June 4, he publicly accused the Federal Security Service of harassing Russian youth groups that did not display government-approved ideological bents. Two days later, after passing customs, passport and security controls at Sheremetyevo Airport in Moscow, he was approached by some 10 security officers as he sat in a boarding lounge, awaiting a flight to Washington. He was taken away and interrogated for five hours and his airline ticket and $3,000 in cash were seized.

The next day he made his trip to Washington. In a telephone interview from Washington, he insisted that he had violated no rules, but that when he arrived home from the airport he was unable to make telephone calls and that when his Washington host called him, the line went dead in midconversation.

Michael McFaul, a scholar at the Carnegie Endowment for International Peace who had invited Mr. Grigoryants to a Washington seminar discussing Russia's decade of independence, was the caller. In an interview, he said the incident fit a pattern of increasing surveillance and harassment.

"As for what has concretely happened, the incidents are few," he said. "But the atmosphere they have created is one of paranoia." People were now worrying about what would happen to them, he said, adding: "They have a lot more to lose now. It's amazing how fear can make you do certain things."