MOSCOW — Russia’s Prosecutor General took control of the investigation into the killing of award-winning journalist Anna Politkovskaya, a critic of President Putin, after she was shot in Moscow on Saturday.

Politkovskaya, whose books include “Putin’s Russia: Life in a Failing Democracy” and “A Dirty War: A Russian Reporter in Chechnya,” was found shot dead at the entrance to her apartment building on Lesnaya Ulitsa, a couple of miles from the Kremlin. She was 48.

“The Prosecutor General of Russia, Yuri Chaika, has taken under his personal control the criminal investigation into the murder,” the prosecutor’s office said on its Web site.

“This decision was taken by the Prosecutor General in connection with the special significance and broad social resonance of the case,” the statement said, adding that the probe is considering Politkovskaya’s “professional activity.”

State television showed grainy footage of a young man wearing a baseball cap entering Politkovskaya’s building and said police wanted to question him in connection with the murder.

“She attacked Russian officials for being brutal and unfair to Chechens, especially women and children,” the director of the World Security Institute and a friend of Politkovskaya, Nikolai Zlobin, said. “She never cared about financial satisfaction, but about justice.”

“She defended the poor and miserable,” Novaya Gazeta editor Dmitry Muratov said in remarks shown on state television today.

A career journalist, Politkovskaya rose to fame with her reports of human rights abuses in Chechnya, a Muslim republic in Russia’s south. Russia sent troops into Chechnya for a second time in 1999 as local rebels sought to set up a separate Islamic republic.

Politkovskaya has worked since 1999 at Novaya Gazeta, a pro-democracy paper that is partly owned by Mikhail Gorbachev, the last president of the Soviet Union, and billionaire deputy Alexander Lebedev. In 2000, she was awarded the Golden Pen Award by the Russian Union of Journalists.

She was held by Russian troops in Chechnya in 2001 and poisoned in 2004 on her way to the hostage-taking in Beslan, near Chechnya, where about 330 people, including children, were killed.

In “Putin’s Russia,”Politkovskaya criticized the Russian president for stifling dissent and other civil liberties.”A Dirty War” described in detail the chaos in Chechnya, including kidnappings and corruption. Politkovskaya’s articles criticized Prime Minister Kadyrov of Chechnya, accusing forces that he controls of ransom kidnappings. Chechnya was living in the “Middle Ages,”she wrote in an article on November 17.

“I have wondered a great deal about why I have so got it in for Putin,”she speculates in “Putin’s Russia.””What is it that makes me dislike him so much as to feel moved to write a book about him?” She partly answers her own question by saying “Putin, a product of the country’s murkiest intelligence service, has failed to transcend his origins and stop behaving like a lieutenant-colonel in the Soviet KGB. He is still busy sorting out his freedom-loving fellow countrymen; he persists in crushing liberty just as he did earlier in his career.”

The Novaya Gazeta Web site devoted pages to the murder yesterday, led by the one-word headline “Anya” and a full-page photograph of Politkovskaya at her desk. “While there is Novaya Gazeta, her killers will not sleep peacefully,” the newspaper said. The murder is the third killing in weeks. Enver Ziganshin, the chief engineer of BP Plc’s Russian gas unit, OAO Russia Petroleum, was shot and killed in Irkutsk on September 30. Russian central banker Andrei Kozlov, who led a fight against corruption in the nation’s banking industry, was assassinated on September 14.

Violence against journalists in Russia is “frequent and impunity prevails,” Paris-based Reporters Without Borders concluded in its annual survey this year.

Paul Klebnikov, the American-born editor of Forbes Magazine in Russia, was shot dead in Moscow in July 2004. Klebnikov was at the time the 11th journalist to be murdered in a contract-style killing since Mr. Putin took office in 2000. No one has been brought to justice in any of the killings, according to the New Yorkbased Committee to Protect Journalists.

“People sometimes pay with their lives for saying out loud what they think,” Politkovskaya told a conference on press freedom in December in Vienna. “People can even get killed just for giving me information.I am not the only one in danger.”