1 policeman and 3 of the gunmen were killed during a siege of a Serbian Orthodox monastery

Kosovo and Serbia have traded accusations over a deadly stand-off between ethnic Serb gunmen and police in northern Kosovo.

One policeman and three of the gunmen were killed during a siege of a Serbian Orthodox monastery in Banjska village on Sunday.

Kosovo's PM Albin Kurti accused Serbia of supporting the armed group.

Serbian President Aleksandar Vucic said Kosovo officials bore ultimate responsibility for the deaths.

He said the three gunmen killed were Kosovo Serbs.

Sunday's clash marks one of the gravest escalations in Kosovo for years, and follows months of mounting tension between the two sides.