Suspect may have held grudge against Yushenkov, say sources

Mr Yushenkov was gunned down in broad daylight near his home on the outskirts of Moscow last Thursday in an apparent contract killing.

The man being held is being described as a 20-year-old who may have blamed Mr Yushenkov over the jailing of his father.

Investigative judges who make 4,000 roubles (120 euros) a month are up against well-armed and well-trained killers Gennady Seleznyov Speaker of parliament

Russian prosecutor-general Vladimir Ustinov and security services chief Nikolai Patrushev later presented their initial findings on the murder to the lower house of parliament, the Duma.

The session was held behind closed doors, but reports said rival members of parliament joined forces to accuse the interior ministry and justice system of being unable to solve the murder.

"Our security forces are in a pitiful state," Gennady Seleznyov, speaker of the Duma, told journalists.

"Investigative judges who make 4,000 roubles (120 euros) a month are up against well-armed and well-trained killers."

The suspect was detained at a flat in Moscow.

Sources say the man's father had written a letter criticising Mr Yushenkov.

Correspondents say the killing of Mr Yushenkov, a leading liberal, stunned Russia's political elite and sparked calls for an end to the climate of impunity that has often surrounded political killings.

Asylum claim

Hundreds of people attended Mr Yushenkov's funeral in Moscow.

Mr Yushenkov had been planning to lead his new party into the December parliamentary election.

A female aide has requested political asylum in the United States, believing 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.

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