Vienna - The man who shot dead a Chechen refugee in the Austrian capital is still on the run, the Vienna prosecution said Monday, a day after the arrest of a second suspect in Poland was announced.

Polish police arrested a 31-year-old Russian of Chechen origin near Warsaw on Thursday, on suspicion that he took part in the murder of Umar Israilov, 27, who had sought court action against Chechen President Ramzan Kadyrov.

While the detained man, Turpal Ali J, is not thought to have shot Israilov himself, he is suspected of having helped carry out the execution-style killing on January 13 together with a second man who is still at large, prosecution spokesman Gerhard Jarosch said.

J, whose full name was not revealed for legal reasons, could be extradited to Austria within the next few weeks, Jarosch said.

The family of the victim has suggested that Israilov was killed on direct orders from Kadyrov. Israilov, a former separatist fighter, sought court action against the pro-Moscow Chechen president for allegedly having tortured him.

Four Chechens remain in Austrian custody for possible involvement in the crime, although they are not prime murder suspects. (dpa)