Yushenkov: a veteran liberal from a military background

Fellow politicians, human rights activists and ordinary citizens paid their last respects as his body lay in state in a cultural centre off the city centre.

Yushenkov, a veteran liberal who was planning to lead his new party into the December parliamentary election, was gunned down in broad daylight near his home on the outskirts of Moscow on Thursday in an apparent contract killing.

A female aide to Yushenkov has requested political asylum in the United States in the belief that his death was linked to his efforts to prove that a series of devastating bomb attacks in 1999 were the work of the Russian secret police.

Colleagues and friends of the late MP expressed outrage at the murder as mourners gathered at the Palace of Youth on Moscow's Komsomolski Avenue before the burial at the Vagankovo Cemetery.

Yushenkov, 53, leaves a wife and two children

"We live in a country where despicable actions go unpunished," said Viktor Pokhmelkin, a fellow leader of Yushenkov's Liberal Russia Party.

Boris Nemtsov, the former deputy prime minister and one of the country's most prominent MPs, described his late colleague as a "calm, incorruptible, and honest politician".

"We should do everything we can so that, for once, the scoundrels are found," he said.

"His despicable murder happened because there is complete impunity, because the government is completely helpless."

The army provided an elaborate guard of honour for Yushenkov, a former colonel.

Bomb probe

The Russian authorities have not announced any arrests in connection with the assassination although Interior Minister Boris Gryzlov said some progress had been made in the investigation.

According to a press release issued by Ms Morozova's lawyer in America, she believes Yushenkov's murder was linked to his insistence that the Federal Security Service (FSB) was responsible for the explosions in Moscow.

There is no doubt in my mind that Sergey Yushenkov was killed because of his investigation of the Moscow bombings Alyona Morozova

Her mother was killed by one of the bombs which went off in an apartment block in the south of the city.

The attacks, blamed by the Russian authorities on Chechen separatists, largely swayed public opinion behind a new war in Chechnya later that year.

In 2002, Ms Morozova helped arrange in the US Congress a screening of a film expounding this theory, which was promoted by exiled Russian tycoon Boris Berezovsky.

Miss Morozova said that, after the film was shown, Mr Yushenkov told her that the FSB was enraged by their actions and he feared they would try to "get even, sooner or later".

However, the BBC's Stephen Dalziel notes that some Russian commentators suggest the assassination is more likely to be linked to internal political rows.