**Russian PM Vladimir Putin has called for tough measures against those behind the bombing of a Moscow-St Petersburg train in which 26 people died.**He said the attack showed the threat to Russia from terrorism remained high.
He was speaking during a TV phone-in, in which he will answer some of half-a-million questions submitted by viewers.
A North Caucasus Islamist group has claimed responsibility for Friday’s attack on the Nevsky Express, some 400km (250 miles) north-west of Moscow.
“It is necessary to act in a very tough way against criminals who carry out these kinds of terrorist attacks,” Mr Putin said.