The supreme court of Belarus on Thursday sentenced two young men to death for staging a Minsk metro bombing in April that killed 15 people in the country's worst post-Soviet era attack.

"The court believes that (they) pose an exceptional danger to society and thus require the ultimate punishment," the judge told the court.

The same judge had earlier found Dmitry Konovalov guilty of "terrorism" and Vladislav Kovalyov of failing to report the bombing plot to the police.

The sentence must still be signed by President Alexander Lukashenko and cannot be appealed. Belarus is Europe's only country to still carry out state executions and was last reported to have put two men to death in July.

The strongman leader of Belarus had earlier said he wanted the two 25-year-old factory workers from the town of Vitebsk to face the brunt of the law.

The same court also found the two guilty for their roles in a bomb attack at Independence Day celebrations in Minsk in 2008 as well as several attacks in their native city of Vitebsk in 2005 that injured more than 100 people.

"Issuing its sentence to Konovalov, the court took into consideration that he has been committing crimes for a long time and that he still had lots of explosives for making new bombs at his (home) lab," judge Alexander Fedortsov told the packed courtroom.

Konovalov had admitted guilt at the start of the trial while Kovalyov recanted his testimony and told investigators that he heard his friend being beaten during interrogations.

But one top Belarus security official who fled into exile to Germany and some local opposition members said they suspected the two had been set up by KGB secret police.

The UN Security Council at the time of the bombing issued a cautious statement condemning the "apparent" terrorist attack.

The second suspect's mother, Lyubov Kovalyova, had sent an impassioned open letter to Lukashenko on the eve of the verdict asking his to show compassion in the case.

"I strongly urge you not to hurry, to think about it, to weigh all the arguments," the suspect's mother wrote. "After all, a single stroke of the pen can claim the lives of two completely innocent young men."

But Lukashenko—who enjoys unprecedented powers in the nation of 10 million and is in total control of the court system—said earlier this month that he wanted to see the suspects punished in full.