Chechen separatist leader Zakayev arrested in Poland
Chechen separatist leader Akhmed Zakayev has been arrested in Poland after travelling there to attend a two-day Chechen congress.
Police questioned him for six hours after acting on an international warrant issued by Russia which wants him extradited on terrorism charges.
He was stopped in Warsaw on his way to see prosecutors, saying he wanted to clarify reports of the warrant.
But a BBC correspondent says Poland is unlikely to extradite him.
He was granted asylum in Britain seven years ago and is seen as a leader of the moderate wing of the Chechen separatist movement.
In exile, he has travelled frequently in Europe, including to Poland.
The Polish government said it had had to take action because Interpol had put Mr Zakayev on its most wanted list, at Russia's request.
Moscow wants to try him on charges of murder, kidnapping and terrorism.
The congress is expected to attract some 200 Chechens to Pultusk, around 40 miles (60km) north of the capital.
A police spokesman said Poland had had no choice but to detain Mr Zakayev.
"He was arrested by plain clothes police as he was leaving a building," Mariusz Sokolowski told Polish television.
Speaking on Thursday, Polish Prime Minister Donald Tusk said that if the Chechen separatist leader were to be arrested, the courts might not agree to extradite him to Russia.
"The extradition procedure isn't the same as extradition," he told Polish media.
Polish Finance Minister Jan Rostowski said that even if the courts did grant extradition, the government could still intervene.
"I can't imagine Zakayev would be handed to Russia. If a Polish court decides to extradite him, the justice minister's agreement is still required," he told Polish radio.
News of his detention was welcomed in Russia.
The head of the Duma's (lower parliament) international affairs committee, Konstantin Kosachev, said it showed that Poland was serious about its international obligations.
"I am sure that an absolutely unbiased and objective judicial inquiry concerning him would be carried out in Russia," he said.
Mr Zakayev has served as a representative of the Chechen government in exile in the West since it was ousted by Russian military action in 2000.
Poland has been among the fiercest critics of Russian policy in Chechnya, although relations have warmed since the death of President Lech Kaczynski and other senior officials in an air disaster earlier this year.
Akhmed Zakayev's position as leader has been called into question by other Chechen separatists.
He is seen as a moderate and earlier this year called for negotiations with Russia, describing Chechen independence as "not an end in itself".
A sharia court formed by the separatist warlord and self-proclaimed emir of the "Caucasus Emirate", Doku Umarov, declared him an apostate last year and sentenced him to death.