At least 30 mourners at a funeral have been killed by a suicide bomber in northwest Pakistan.More than 50 others were wounded at the ceremony to bury the Shit-ite muslim leader Sher Zeman, who was assassinated yesterday. A thousand people had gathered in the town of Dera Ismail Khan. One witness said: “A man appeared from the Rawalpindi bus-stop. I was coming from the intersection when the bomb exploded. We all hit the ground and afterwards cleared the bodies and carried the injured to hospital.” Dera Ismail Khan is close to the Waziristan region on the Afghan border where there is strong support for the Taliban and al-Qaeda. The town has been the scene of ongoing sectarian bloodshed between rival Shi-ite and Sunni militant groups. After the bombing mourners responded with machine-gun fire and rioting before Pakistani troops and police imposed a curfew.