Two suspects from the Northern Caucuses, a Russian territory which is home to violent separatists, heave been arrested as possible culprits in the murder of Boris Nemtsov.
Nemtsov, a harsh critic of Russian President Vladimir Putin was shot four times in the back as he crossed a Moscow bridge with a female companion .
Accusations on who is responsible for the murder have ranged from governmental agents to Muslim extremists to members of the oppositional party themselves.
The names of the suspects have yet to be released.
