Alexandra Shevchenko, Anna Hutsol and Yana Zhdanova "have fled Ukraine fearing for their lives and for their liberty," according to a statement published on Femen's website on Saturday.

The Femen statement said the trio decided to leave Ukraine after police called them in for questioning on Friday. Femen also said its founding memebers would "continue their activities in Europe," without saying where they had gone.

On Tuesday, police said they found a handgun and a hand grenade during a search of Femen's Kyiv office. Authorities had said they dispatched a group of explosives experts to the premises after an anonymous tip-off. Femen is now facing an official investigation.

The protest group said it possessed no weapons, and accused the authorities of planting the weapons in a bid to shut down the organization. Femen subsequently announced it was leaving its Kyiv office, saying they believed the building had been bugged by police.

Femen, best known for its bare breasted political protests, was founded in Ukraine but has since set up a headquarters in Paris. Russian President Vladimir Putin has become a frequent target of Femen protests, especially since the imprisonment of the Russian punk group Pussy Riot last year.

The group has also claimed that Hutsol and other members were beaten last month by special service agents who were trying to make them cease their activities. Femen alleged that the agents were "commissioned by Presidents Putin and Yanukovych," referring to Ukrainian President Viktor Yanukovych.

msh/ch (AFP, dpa, Reuters)