Her Moscow newspaper yesterday defied the hitmen by publishing Ms Politkovskaya’s final, unfinished, article and pledged to continue her crusade.

The article in Novaya Gazeta detailed evidence of torture on civilians by police in Chechnya, including stills from a video showing assaults on two unidentified victims. One man said that he was beaten, given electric shocks and almost suffocated in a Chechen government office until he confessed to murders he did not commit.

The article reproduced a letter from a Chechen man called Beslan Gadayev, who writes that he was extradited from Ukraine and handed over to law enforcement officers in the Chechen capital, Grozny.

“I swore I had killed no one,” the letter read. “They said: ‘No, you have killed’.”

Mr Gadayev wrote that he was punched twice in the face then handcuffed and suspended from a length of pipe between two filing cabinets in an investigator’s office.

“They attached wires to my little fingers. Seconds later they started to give me electric shocks and at the same time beat me with rubber truncheons,” he said. “I do not know how long this went on for.” The report said that Mr Gadayev confessed soon afterwards to taking part in an armed attack on police and is now in prison awaiting trial.

Ms Politkovskaya, who was 48, wrote: “When prosecutors and judges work not for the law and punishment of the guilty, but on political orders and in pursuit of anti-terrorist aims that are pleasing to the Kremlin, then criminal cases multiply like hot cakes.”

Novaya Gazeta also published grainy pictures taken from a video in Ms Politkovskaya’s possession which, it said, showed Chechen security forces swearing at two young men, one of whom was covered in blood.

The newspaper said she was planning a second report to accompany the video but was killed before she could write it.

It remains unclear whether Ms Politkovskaya was murdered because of her final article or whether hitmen were taking revenge for a body of work that has persistently challenged Moscow’s account of the insurgency in Chechnya.

The newspaper noted at the end of her story: “Politkovskaya’s material was interrupted here. It is not finished. What episodes remained beyond the limits of the text?” Her murder has been one of a series of high-profile contract killings in the past month and has coincided with a campaign of official persecution against Georgians living in Russia in a row over spying. Opponents of President Putin fear that dangerous emotions are being stirred up before a key election period that will determine who succeeds him in the Kremlin in 2008.

They say that a vengeful mood in Russia and the sense that anybody can be killed is creating an atmosphere of repression in which people are afraid to speak their minds. One ultranationalist group has urged supporters to kill 89 people whose names have been posted on its website. Ms Politkovskaya’s death followed the murder in Moscow of Russia’s top banking regulator, Andrei Kozlov, last month. A hitman shot dead another banker, employed at the country’s second-largest bank, on Tuesday.

Garry Kasparov, the former world chess champion and a vocal opponent of Mr Putin, said yesterday that he also feared for his life. At a conference in Portugal he said: “I try to protect myself and my family as much as possible but I am aware that no protection is possible. Putin’s regime is seen in the West as a strange democracy, a Russian-style democracy. But in reality it is a police state. And the sooner Putin leaves, the better off the country will be.”

The Kremlin’s confrontation with Georgia, its former Soviet satellite, has provoked accusations from human rights groups of totalitarianism.

Lilia Shevtsova, who, like Ms Politkovskaya, has written a book on Mr Putin’s Russia, told The Times that the authorities were playing on a tradition of Russian xenophobia. “Anna was killed in an atmosphere when people started to hate each other and to look for enemies, particularly in the Caucasus,” said Dr Shevtsova, a senior analyst at Moscow’s Carnegie Centre.

Ms Politkovskaya was one of the few journalists willing to criticise Mr Putin openly and to investigate atrocities in Chechnya, the north Caucasus conflict that propelled him into the Kremlin in 2000. Many at her funeral on Wednesday saw her death as the extinction of liberal dissent. Many in Russia believe that her brave reporting was the reason Ms Politkovskaya was killed on Saturday — Mr Putin’s 54th birthday.

The published fragment did not, however, link Ramzan Kadyrov, the Chechen Prime Minister, directly to the allegations as some had thought it would. Mr Kadyrov has denied any involvement in the murder.

In a radio interview two days before she died Ms Politkovskaya implicated a private militia controlled by Mr Kadyrov in killings. She said: “I am conducting an investigation about torture today in Kadyrov’s prisons. These are people who were abducted . . . for completely inexplicable reasons and who died.”

Whether she was killed to prevent publication of vital information remains unknown. But the murder has made most Russian journalists — already cowed by 42 contract-style killings since 1992 — even less willing to ask awkward questions.

Ms Politkovskaya is the third journalist at Novaya Gazeta to be killed and the paper has offered 25 million roubles (£500,000) for information about her killers. Few in Russia expect them to be found despite Mr Putin’s insistence in Germany this week that they would not go unpunished.

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