MOSCOW - Under pressure to solve the contract-style killing of journalist and Kremlin critic Anna Politkovskaya, Russia's chief prosecutor announced Monday the arrest of 10 suspects, including a Chechen crime boss and five law enforcement officers.

Prosecutor General Yuri Chaika refused to say who was suspected of ordering the Oct. 7 shooting of Politkovskaya, whose tireless chronicling of the killings, kidnappings and torture of civilians in war-scarred Chechnya had angered the Kremlin and the Moscow-backed Chechen leadership.

But he said that only someone living outside Russia would have an interest in killing Politkovskaya, with the aim of discrediting President Vladimir Putin and destabilizing the country ahead of national elections.

The prosecutor appeared to be referring to tycoon Boris Berezovsky, a former Kremlin insider who is one of Putin's fiercest critics and lives in Britain, where he has refugee status.

In implicating Russia's enemies abroad, Chaika echoed statements by Putin shortly after Politkovskaya's death that "people who are hiding from Russian law enforcement have been hatching plans to sacrifice someone and create an anti-Russian wave in the world."

The Kremlin has pointed the finger at Berezovsky in this and other killings that have gained worldwide attention and blackened the reputation of Putin's Russia.

Berezovsky said Monday the effort to link him to Politkovskaya's death was a "hysterical reaction" to his criticism of Putin.

Chaika's conclusion was met with some skepticism by media rights organizations and editors at Politkovskaya's newspaper, Novaya Gazeta.

"Contrary to what the prosecutor general says, there were people inside the country interested in silencing her, and the investigation should be looking into this," Reporters Without Borders said in a statement.

Sergei Sokolov, deputy chief editor of Novaya Gazeta, welcomed the arrests but expressed concern the case would be used for political purposes ahead of December parliamentary elections and a presidential vote in March.

"Of course ... we are concerned that in an election year, this crime may be used by different groups for their own aims," Sokolov said. "That, unfortunately, is our Russian illness and the way things work here."

Chaika said Politkovskaya's slaying was set up by a Chechen native who led a Moscow organized crime ring that specialized in contract killings. He said that those arrested included a police major and a Federal Security Service officer, as well as three former police officers, who were accused of tracking Politkovskaya and providing her killers with information. The suspected gunman was among those arrested, he said.

The prosecutor said that people involved in killing the 48-year-old Politkovskaya at her apartment building in Moscow may have also been involved in the 2004 shooting death of Paul Klebnikov, an American who was editor of Forbes magazine's Russian edition.

"As for the motives for the killing, the results of the investigation lead us to the conclusion that only individuals located outside the territory of the Russian Federation could have had an interest in getting rid of Politkovskaya," Chaika told a news conference.

"It is in the interest first of all of those people and structures that aim to destabilize the situation in the country, change the constitutional order (and) create a crisis in Russia," he said, adding that such forces want to "discredit the leadership" and put foreign pressure on the Kremlin.

They seek "a return to the former system of rule, under which money and oligarchs decided everything," he said.

Chaika did not name those arrested. He said Politkovskaya knew the person who ordered the killing and had met with him.

The Federal Security Service identified its arrested officer as Lt. Col. Pavel Ryaguzov.

Among those arrested are three brothers from Chechnya, the Interfax news agency reported, citing the lawyer for one of them. The lawyer expressed fears that "this could be another case with predetermined culprits," the report said.

Ramzan Kadyrov, the Chechen president, said he had been informed of their arrest. "I think that law enforcement agencies should have dealt with them long ago," Interfax quoted him as saying while on a visit to Jordan.

Much speculation about Politkovskaya's slaying has focused on Kadyrov, who was prime minister of Chechnya when she was killed and became president in March. He has denied involvement.

Politkovskaya had been a consistent critic of Kadyrov, accusing his security forces of kidnapping and torturing civilians. She also had reported on brutal treatment of civilians by Russian troops in Chechnya.

Politkovskaya's killing came less than two months before the radiation poisoning death in London on Nov. 23 of Berezovsky associate and former KGB counterintelligence officer Alexander Litvinenko, which further damaged the Russian leadership's reputation abroad.

Litvinenko, who had been investigating Politkovskaya's death, had said Putin was behind her slaying and also blamed the Russian leader for his own poisoning. The Kremlin has tried to shift the blame for Litvinenko's death onto Berezovsky.

Chaika's remarks were the first announcement of arrests in the killing, which Western governments have urged Russian authorities to solve.

Nancy Beck, a State Department press officer, said the United States was encouraged that Russia was taking action in the case. "We'll wait and see what all the details are before commenting further."

Reporters Without Borders said it hoped the announcement has not been made solely to defuse questions from those who want the case solved. "We have in the past seen announcements by the Russian authorities that have been made just for effect," its statement said. "And most of the investigations into the murders of journalists have never been concluded."

The U.S.-based Committee to Protect Journalists said Politkovskaya was the 13th journalist killed in a contract-style murder in Russia since Putin took office in 2000, and nobody has been convicted in any of them -- a record that has led to doubts about the government's dedication to freedom of the press.

Alexei Simonov, chairman of the Glasnost Defense Foundation, a leading Russian media rights watchdog, said he and the staff of Novaya Gazeta knew of the arrests a week ago.

"I think these are serious arrests based on real evidence," Simonov said. He said he was confident investigators had tracked down Politkovskaya's killers, but he expressed concern that the truth about who was behind the slaying could prove more elusive.

Simonov said the staff of Novaya Gazeta feared authorities would try "to steer the case in the direction of London" and blame Politkovskaya's killing on Berezovsky.