Hundreds of mourners have attended the funeral in Moscow of the investigative reporter Anna Politkovskaya who was killed on Saturday.
A woman lays flowers at the coffin of Anna Politkovskaya
The 48-year-old - a critic of President Vladimir Putin - was found shot dead at her apartment building.
One of her former editors described Ms Politkovskaya as a fearless person whose death was a blow to the freedom of the press in Russia.
President Putin said the "horribly cruel" crime must not go unpunished.
Ms Politkovskaya was one of the few Russian journalists to write about human rights abuses in Chechnya, and many Russians believe her murder was a contract killing.
Speaking at the funeral, Vitaly Yaroshevsky, deputy editor-in-chief of Ms Politkovskaya's newspaper Novaya Gazeta, said: "There are almost no more journalists like her left today.
"Anna was a fearless person; not reckless, but courageous. She's the third one to have died from our paper.
"This is a blow to freedom of the press in Russia."
Speaking during his visit to Germany, Mr Putin said Russian authorities would strive to find and punish the perpetrators.
"Whoever has committed this crime and whatever their guiding motives, we should state that this is a horribly cruel crime. It must not remain unpunished, of course."
Anna Politkovskaya's death was marked in Bulgaria and Ukraine
But he played down the significance of Ms Politkovskaya's work.
"This journalist was a severe critic of the incumbent authorities in Russia; she was well known among journalists and human rights campaigners and in the West. However, her influence on the country's political life... was minimal."
According to the Tass news agency, Duma speaker Boris Gryzlov pledged to investigate the killing through parliamentary channels.
Russia guaranteed freedom of the press and freedom of speech, and "such atrocious criminal actions cannot ban this," he said.
Mourners, including friends, relatives and fellow journalists, walked past Ms Politkovskaya's coffin before the burial at the Troyekurovskoye cemetery on the outskirts of Moscow.
On Monday, well-wishers laid flowers by photographs at a makeshift shrine in front of her apartment building and Russia's main newspapers ran pictures of her on their front pages.
Colleagues at her newspaper, Novaya Gazeta, published a special issue promising that "her killers will not sleep soundly" and the paper has offered a $1m (£534,000) reward to solve the murder.
SUSPECTED CONTRACT KILLINGS
October 2006 - campaigning Russian journalist Anna Politkovskaya shot dead in Moscow
Sept 2006 - first deputy chairman of Russia's central bank Andrei Kozlov shot dead in Moscow
Oct 2005 - former bank head Alexander Slesarev gunned down near Moscow
July 2004 - US editor of Forbes' Russian edition Paul Klebnikov shot dead in Moscow
Oct 2002 - Magadan governor Valentin Tsvetkov killed in Moscow
Nov 1998 - liberal MP Galina Starovoitova killed in St Petersburg
March 1995 - leading journalist Vladislav Listyev shot dead in Moscow
Russia's top prosecutor is personally leading the official investigation, focusing on her investigative reporting as a possible motive for the crime.
The BBC's Richard Galpin in Moscow said there will be international pressure to solve this case and others.
"The pressure is now going to be applied on the Russian government by the international community to put an end to the killing of so many journalists," he said, citing research showing that more 40 journalists have died since the early 1990s, many in apparent contract killings.
Ms Politkovskaya's body was found in a lift at her block of flats. Grainy CCTV footage shows a man in a baseball cap following her inside just before the shooting.
Ms Politkovskaya had accused Russian security forces in Chechnya of abusing human rights but Chechnya's pro-Moscow leaders have condemned her murder.