Russians Say Terrorists Downed at Least One Jet

MOSCOW —  Russian authorities announced Friday that “a terrorist act” had brought down at least one of two airliners that crashed this week, and investigators raised suspicions that two Chechen women aboard the flights might have been suicide bombers.

Investigators have found “traces of an explosive substance” of a type previously used by Chechen guerrillas in the wreckage of one plane, said Sergei Ignatchenko, a spokesman for the Federal Security Service, or FSB.

“According to preliminary information, at least one of the air crashes, that in the Rostov region, has been the result of a terrorist act,” he told Russian news agency Itar-Tass.

Officials previously said that terrorism was one of many possible causes being investigated in the Tuesday night crashes, which came minutes apart. Officials have revised the death toll to 90.

Meanwhile, a militant group identifying itself as the Islambouli Brigade claimed responsibility Friday for the crashes in a statement on a website linked to Islamic radicals. There was no way to authenticate the claim.

The twin tragedies came amid fears that rebels in Russia’s southern republic of Chechnya, who seek independence for the war-torn region, might launch attacks before Sunday’s election there to replace the pro-Kremlin president, who was assassinated in May. A Moscow-backed candidate is expected to win.

The FSB, the main successor to the Soviet-era KGB, expressed suspicion Friday about the two Chechen women, Itar-Tass reported.

One, identified as S. Dzhebirkhanova, reportedly checked in for the Sibir Airlines Tu-154 flight from Moscow to the Black Sea resort of Sochi, which crashed near the southern city of Rostov-on-Don, the news service reported.

The second woman, Amanta Nagayeva, was on the passenger list for the Volga-Aviaexpress Tu-134 flight from Moscow to Volgograd, which crashed about 100 miles south of Moscow.

Authorities said no one had come forward to claim either body.

In Washington, White House Press Secretary Scott McClellan said evidence was growing that the crashes were “acts of terrorism.”

Security officials said this week that they had not immediately found evidence of terrorism, though both planes’ tail sections landed hundreds of yards from the fuselages.

But Gazeta, a Russian daily newspaper, reported Friday that investigators were misled because there were no traces of explosives in the passenger areas or cockpits. They then focused on holes in the hulls of both planes where the toilets had been and on the theory that small explosions in those areas had brought the planes down, Gazeta said.

The FSB said it discovered traces of an explosive, evidence that a bomb did bring down the Tu-154. Preliminary analysis indicates that the explosive is hexogen, said Ignatchenko, the FSB spokesman. That is the substance used in a series of Russian apartment building bombings in 1999, which authorities attributed to Chechen terrorists and cited as partial justification for launching the current war against separatists.

In the Chechen capital of Grozny, police said they were seeking information about the two women but had not reached any conclusions.

“We have started working, and people are working fast. We will establish the addresses. We will find their friends, their acquaintances, and by tomorrow afternoon, I assure you, we will know what kind of people these women were,” Chechen Interior Ministry spokesman Ruslan Atsayev said.

“Until then, we can’t make any conclusion,” he said.

Russian President Vladimir V. Putin, who was prime minister at the time of the 1999 apartment bombings, won popularity with his get-tough response, which helped propel him to victory in his first presidential bid the following year. But the FSB has never been able to put to rest the belief among some Russians that the agency played a role in the bombings.

That is partly because the bombings, by triggering Russian outrage, brought political benefit to Putin, and partly because of a notorious incident in which FSB agents were caught in September 1999 placing what appeared to be explosives in an apartment building in the city of Ryazan. The agency acknowledged that the men were its agents but said they had put sacks of sugar in the building as part of a training exercise.

Liliya Shevtsova, a political analyst with the Carnegie Moscow Center, noted that the discovery of hexogen calls up memories of the 1999 bombings. “But today such tragedies are absolutely not favorable for Putin,” she said.

In Chechnya, several police officers on the street privately expressed skepticism Friday that terrorists were behind the jetliner crashes. Some brought up the 1999 blasts and hinted that Russian agents might have downed the planes to build support for the Kremlin in Sunday’s presidential election.

“I don’t think it was a Chechen. Maybe they themselves set it up and not Chechen terrorists. Like the apartment houses,” said one officer, who identified himself only as Amruddin.

Another officer in Grozny, who gave his name only as Rashid, said he believed that “somebody definitely wants to pump up tensions. I think those who profit from the war did it.”

Even a senior Interior Ministry official, who spoke on condition of anonymity, expressed similar suspicion. “The story doesn’t correspond to reality,” he said. “It’s a pure provocation.”

The Chechen government said it had no information on the investigation.

Throughout Grozny, there were fears that the investigation’s findings would spark reprisals by the Russian government and further crackdowns on traveling Chechens, who often undergo heavier-than-normal searches and document checks.

“I myself often fly planes, and my friends and my colleagues too,” said Atsayev, the Interior Ministry spokesman. “The worst thing that can happen to me is to find myself in a falling plane and to think that the next morning, I will be on the suspected terrorist list because I am a Chechen.”

“Is Putin such an idiot as to blame us now? What does he get out of it?” said Roman Magomadov, a 33-year-old unemployed man from Grozny.

“We don’t believe it,” said Addam Almurzayev, 30. “They want to find a scapegoat. It’s a method they have used many times.”

Holley reported from Moscow and Murphy from Grozny. Yakov Ryzhak of The Times’ Moscow Bureau contributed to this report. Associated Press was used in compiling it.