MINSK (Reuters) - Belarus has executed one of two men convicted for a fatal 2011 metro bomb attack, despite protests from European human rights groups and calls for a re-trial, a relative of the executed man said on Saturday.
The execution is likely to further sour already strained relations between the former Soviet republic and the European Union whose ambassadors left Belarus this month in a diplomatic row triggered by fresh EU sanctions.
Belarus is the only country in Europe to retain the death penalty and rights groups had urged it not to carry out the death sentences on two 25-year-old factory workers, Vladislav Kovalyov, whose execution was reported on Saturday, and Dmitry Konovalov, whose fate is not yet known.
"I condemn the execution of Vladislav Kovalyov and regret that Alexander Lukashenko has ignored all international appeals to waive the death penalty," German Foreign minister Guido Westerwelle said in a statement on Saturday.
"I urge the Belarus leadership not to execute the other man charged, Dmitry Konovalov."
Konovalov and Kovalyov were sentenced last November for carrying out the attack at the "October" metro station at rush hour in central Minsk which killed 15 people and wounded dozens more.
"We received a letter from the Supreme Court this morning ... saying that the sentence had been carried out," Tatyana Kovalyova, the dead man's sister, told Reuters.
"The letter was dated March 16. They did everything very quickly."
Konovalov's family has declined to talk to the media and it was unclear whether he had also been executed.
At his trial, Kovalyov said he had never confessed and had only agreed to testify against his childhood friend Konovalov after hearing his screams from a nearby jail cell. After being convicted he asked President Alexander Lukashenko for clemency.
Earlier this week, Lukashenko said he had refused to pardon the two, citing the gravity of the crime.
Lukashenko, an autocratic leader in power since 1994, has kept his country out of the European mainstream. Belarus' relations with the EU are at a low after a crackdown on political opposition following mass protests against Lukashenko's re-election in December 2010.
On Saturday, European Parliament President Martin Schultz said he was "appalled" by the execution.
"The death penalty is irrevocable, inhumane and degrading," he said.
(Reporting by Andrei Makhovsky; Writing by Olzhas Auyezov; Editing by Robin Pomeroy)