Hundreds of mourners gathered in Moscow Tuesday to pay their final respects to noted investigative journalist and Kremlin critic Anna Politkovskaya.

The 48-year-old mother of two was fatally shot in an apparent contract killing Saturday as she carried groceries into her Moscow apartment.

Several foreign envoys, including U.S. Ambassador William Burns, joined a host of human rights activists at the funeral. Witnesses said there was no sign of any high-ranking Russian government officials at the service.

In Germany, visiting Russian President Vladimir Putin called the murder "an unacceptable crime that can not go unpunished." On Monday, Mr. Putin spoke by phone to President Bush and told him the government will use all necessary measures to find the journalist's killer.

Politkovskaya's murder is the latest in a series of high-profile execution-style killings in Russia. They include last month's assassination of anti-corruption stalwart and Russian central bank chief Andrei Kozlov, and the 2004 killing of Paul Klebnikov - the U.S.-born editor of Forbes magazine in Russia.

At the time of her death, Politkovskaya's newspaper, Novaya Gazeta, was preparing to publish a report from the journalist with witness accounts and photographs of tortured captives in Chechnya.

Her colleagues said Politkovskaya blamed the Chechnya abuses on Moscow-backed Chechen Prime Minister Ramzan Kadyrov.

Mr. Kadyrov on Sunday expressed sorrow for what he called the senseless killing of the journalist.

Russian Prosecutor-General Yuri Chaika has taken personal charge of the murder probe. However, Politkovskaya's colleagues have voiced doubts the murder will ever be solved. The newspaper has offered a $930,000 (25 million ruble) reward for information that will help solve the crime.

Some information for this report was provided by AFP, AP and Reuters.