In pictures: Southern Russia blast

1 of 7 A big operation to look for survivors was mounted after the bomb attack on a Russian military hospital near Chechnya

2 of 7 A lorry packed with explosives reportedly rammed through the gates of Mozdok hospital, North Ossetia

3 of 7 At least 50 people died in the explosion, and others were feared to be trapped under wreckage

4 of 7 More than 100 people were in the building at the time of the attack

5 of 7 The hospital had been treating Russian soldiers serving in Chechnya

6 of 7 Rescue workers stopped looking for more survivors on Sunday

7 of 7 Defence Minister Sergei Ivanov flew to the site accusing officials of negligence