A Russian police patrol has been ambushed in the southern republic of Dagestan.
Five of the officers were killed.
The Russia news agency , ITAR-TASS, said they were ambushed at a police roadblock near the border with Chechnya.
Dagestan, like other parts of the North Caucasus, has been plagued by violence exacerbated by religious and ethnic tensions.
From the newsroom of the BBC World Service