A court Wednesday convicted a man of trying to assassinate President Bush and the leader of Georgia by throwing a grenade at them during a rally last year, and it sentenced him to life in prison.

Vladimir Arutyunian also was convicted of killing a policeman during a shootout while authorities were trying to arrest him several weeks after the May 10, 2005, grenade incident at a rally that drew tens of thousands of people to the capital of this former Soviet republic.

The grenade that Arutyunian threw during the rally attended by Bush and President Mikhail Saakashvili landed about 100 feet from the stage where they were standing behind a bulletproof barrier and did not explode. No one was hurt.

The grenade, which was wrapped in a cloth, apparently malfunctioned, investigators said.

Arutyunian, 27, has acknowledged that he threw the grenade in the direction of the stage and said he would try again to kill Bush if he had the chance.

He was arrested in July on the outskirts of Tbilisi after a shootout that killed one officer and was shown in video broadcast on television as saying from a hospital bed that he had thrown the grenade high with the goal of having it explode so that the bulletproof glass would not block shrapnel.

Bush and Saakashvili learned of the grenade only after the rally.

Arutyunian did not testify during the trial, which began last month. In December, he appeared in court with his mouth sewn shut in what he called a show of solidarity with thousands of inmates conducting a hunger strike in the ex-Soviet republic.

The motivation for throwing the grenade was never clear. He was identified as a member of a party that supported Aslan Abashidze, the former leader of the Adzharia region who was an adamant foe of Saakashvili.

Abashidze was eventually driven from office amid rising protests in the region that echoed the massive Rose Revolution demonstrations that helped bring Saakashvili to power in late 2003.

Arutyunian's lawyer, Elizabeta Dzhaparidze, said after the conviction and sentencing that she would appeal because "I consider that everything was far from proved."

She cited the fact that Arutyunian's fingerprints were not found on the grenade.

However, prosecutor Anzor Khvadagiani said that the grenade being wrapped in cloth explained the lack of distinguishable fingerprints and said that DNA tests of material found on the cloth matched Arutyunian's.

FBI agents assisted Georgian authorities in the investigation, helping to question witnesses and examining evidence.