Warsaw (AFP) - Poland said Friday it would have a British laboratory search for traces of explosives on samples from a 2010 plane crash in Russia that killed 96 people, including then-Polish president Lech Kaczynski.
The state prosecutor's office said the tests would be carried out by the Forensic Explosives Laboratory at Fort Halstead, near London.
The plane was carrying a Polish delegation to a ceremony in Russia's Katyn Forest in memory of thousands of Polish army officers killed by Soviet secret police in 1940.
Poland's previous liberal government blamed the crash on bad weather and errors by the Polish pilots and Russian air traffic controllers.
But the governing Law and Justice (PiS) party, led by the former president's brother, Jaroslaw Kaczynski, believes a fire may have erupted onboard before the crash, possibly the result of foul play.
Warsaw has repeatedly asked Moscow to hand over the wreckage and black boxes of the plane, but each time Russia has said it will do so only when its own inquiry is finished.
In November, Poland began exhuming the bodies of the crash victims, reviving an investigation into the cause of the crash.