Vienna - After a young Chechen refugee was shot execution-style in Vienna, a prosecutor on Thursday did not rule out that the young man said to have been a critic of the Chechen regime was murdered for political reasons.

According to witness reports, two unknown men were involved in the fatal shooting of Umar Israilov, 26, outside a grocery store on Monday. A third man, also a Chechen, was detained as he is suspected of having driven the getaway car.

Austrian and US media reported that Israilov was a former Chechen rebel fighter who later turned bodyguard of pro-Russian Chechen President Ramzan Kadyrov.

In 2006, when Israilov had already fled to Austria, he had reported alleged torture and abductions ordered by Kadyrov to the European Court of Human Rights.

That the Chechen exile fell victim to a politically-motivated murder "could be true, but there is no evidence yet," said Gerhard Jarosch, the spokesman of Vienna's prosecution.

A refugee organization working for Israilov had informed police about this potential threat before the killing, said Walter Nevoral of Vienna's police intelligence unit.

After the murder, "his widow said that he had felt threatened and being watched, in connection with his former political activities," he said.

Since the Chechen conflicts in the 1990s, around 30,000 Chechens have fled to Austria. (dpa)