Hundreds of people rallied in the Chechen capital Tuesday to protest the slaying of a lawyer who opposed the early release of a Russian army officer convicted of strangling an 18-year-old Chechen woman.

A crowd of about 1,500 in Grozny demanded justice following the killing of Stanislav Markelov, 34, a prominent Russian human rights lawyer who had worked with the investigative journalist and Kremlin critic Anna Politkovskaya. She was gunned down in Moscow in 2006.

Markelov was shot on a busy street near the Kremlin on Monday, shortly after speaking to journalists about the case of Col. Yuri Budanov, who admitted killing Heda Kungayeva in 2000. A 25-year-old journalist, Anastasia Baburova, was fatally shot when she tried to intervene after the shooting.

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Budanov, a former tank regiment commander, said he believed the teenager was a rebel sniper in the Kremlin's war against Chechen insurgents. He was freed last week with more than a year left in his 10-year murder sentence. Reviled in Chechnya, he was held up as a heroic patriot by racist nationalists.

Members of the crowd in Grozny's central square carried posters reading "The killer must be punished," "Why does the law not work in Russia?" and "We demand justice!"
"Markelov showed his courage, unlike many others who could not raise their voices to denounce Budanov," Kungayeva's uncle Lecha Kungayev said.

Minkail Ezhiyev — like Markelov, a lawyer for Kungayeva's family — told demonstrators Markelov received threatening calls and text messages from people identifying themselves as supporters of Budanov days before his murder.

"Unfortunately, they carried out their threats," Ezhiyev said.

Investigators said Markelov's work was likely the motive for his slaying, but that it was not clear whether he was shot by a contract killer or an individual acting alone.

"The investigation presumes the murder was carried out either by a professional killer or by a lone criminal who disagreed with Markelov's views," Federal Investigative Committee spokesman Vladimir Markin said.

Markelov was shot in the back of the head at close range by a masked attacker a short distance from Moscow's Christ the Savior Cathedral. Russian television showed his body sprawled in the snow on the sidewalk.

Markelov had just told reporters he was considering challenging Budanov's release in an international court.

Budanov denied involvement in the killings.

"Do you think that after a few days of freedom I had a burning desire to do more time?" he told the daily Komsomolskaya Pravda in an interview.

Budanov's case was closely watched as a test of Russian authorities' determination to punish rights abuses in Chechnya after two wars against separatists, and his early release provoked protests here last week.

Markelov was widely respected in Chechnya as a lawyer for the families of those abducted, tortured or killed by the Russian military and Russian-backed security forces.

The shootings also provoked grief and outrage among beleaguered liberals across a country where lawyers and journalists who challenge the official version of justice are frequently targeted. Dozens of people brought flowers to the site of the killing Tuesday.

"Increasingly, in Russia, lawyers who represent victims of human rights violations, in common with other human rights defenders, face attack and intimidation," the International Commission of Jurists said. "If the rule of law is to be preserved, it is essential that lawyers be able to conduct their work without fear for their safety."

While Markelov was not well known outside Russia, colleagues compared him to Politkovskaya for his courage and dedication to human rights.