Lithuanian prosecutors on Wednesday charged a military medic with spying for neighboring Belarus, in the second espionage case involving the Russian ally in less than a month.

"The suspect accused of espionage worked for the Belarusian secret service," state prosecutor Raimondas Petrauskas told reporters.

The European Union on Thursday extended sanctions against Belarus for an additional year, saying Minsk had not made enough progress on human rights to justify any other course.

The decision was taken "because not all political prisoners have been released ... and respect for human rights, the rule of law and democratic principles has not significantly improved in Belarus," a statement said.

Russia on Thursday signed an agreement with Belarus and Kazakhstan on creating a Eurasian Economic Union designed to strengthen ties between the three ex-Soviet countries.

The agreement was signed by Russian President Vladimir Putin, Belarussian President Alexander Lukashenko and Kazakh President Nursultan Nazarbayev in the Kazakh capital of Astana.

Belarussian President Alexander Lukashenko said Wednesday he would ask Russia to station up to 15 jets in his country in response to NATO's moves over the Ukraine crisis.

"If NATO decided, together with the Americans, to ramp up their air force presence near our borders, what, should we just watch them?" the maverick leader said, speaking at a meeting of his security council.

Belarus said on Friday that its main military court had jailed two Belarussians to eight and 10 years for spying for the neighboring Baltic state of Lithuania.

The Belarussian security service -- still known as the KGB -- said in a statement that a military tribunal had found two men identified as A. Fenzelyau and Ye. Kochura guilty of treason.

Three Baltic NATO states on Friday questioned the purpose of major war games by Russia and Belarus close to their borders, accusing their Soviet-era master Moscow of a secret "anti-West" agenda.

Lithuania, Latvia and Estonia, former Soviet states that are now members of the western alliance, all expressed concern about the scale of military manoeuvres publicly intended to prepare defenses against terrorism.

Belarus must free all political prisoners immediately and cease a litany of abuses including torture, forced labor and flawed trials, the U.N.'s top human rights body said Thursday.

The U.N. Human Rights Council also demanded that the ex-Soviet republic -- whose President Alexander Lukashenko is branded Europe's last dictator by the United States -- cooperates with its investigators.

Sudan breached U.N. sanctions by using warplanes and rockets bought from Belarus and Russia in the Darfur conflict, according to U.N. experts who have called for a tightened embargo.

With the war now a decade old, U.N. sanctions report outlined how the conflict has intensified with government air attacks on Darfur villages, rebels opening military camps in neighboring South Sudan and intelligence agents torturing opposition students with acid.

Police in Belarus are going after gays, raiding their clubs and locking up clubbers overnight, and summoning gay activists for questioning. One activist accuses police of beating him during questioning, while others say they were interrogated about their sex lives. The leader of a gay rights organization was stripped of his passport just ahead of a planned trip to the United States.

That is the government's response to a decision by gay activists across the country to try in January to legally register their rights organization, GayBelarus. It marked a more resolute attempt to emerge from the shadows after being slapped down repeatedly by the authorities.

Belarus has arrested three people after a homemade bomb exploded outside the headquarters of the KGB security service in the northeastern city of Vitebsk, officials said on Monday.

The KGB said in a statement that the "primitive homemade pyrotechnic device" had gone off at 1548 GMT on Sunday evening, damaging two windows of the KGB building.