An ultranationalist who bombed a McDonald's restaurant in central St. Petersburg last year, injuring six people, was jailed for 15 years Monday.

A jury at the St. Petersburg City Court convicted Fyodor Kovalchuk in the Feb. 18, 2007, bombing and ordered him to serve out the sentence in a maximum security prison, Interfax reported.

Kovalchuk was arrested after the attack along with five other ultranationalists suspected in the crime.

Prosecutors classified the attack on the restaurant as terrorism.

Along with Kovalchuk, a second defendant was handed a seven-year suspended sentence for his role in the bombing, Interfax reported.

Over the course of the investigation and trial there were contradictory reports about the motive for the attack.

Investigators told the web site Gazeta.ru shortly after the suspects' detention that the bombing was meant to honor ultranationalist leader Dmitry Borovikov, who was shot dead by police in May 2006 after purportedly resisting arrest.

Prosecutors later said in a statement that "the aim of the explosion in the McDonald's cafe was to express disagreement with the authorities and the existing regime."

But according to national media reports, Kovalchuk testified in court that his attack was triggered by Western media criticism of a speech by Prime Minister Vladimir Putin in which he warned of a new Cold War.

Putin, who was president at the time, made his comments 10 days before the restaurant was attacked on Feb. 18, 2008.

McDonald's restaurants have been frequent targets of anti-globalization protesters and often identified with the United States, where the fast food chain has its headquarters.

(Reuters, MT)