**Rough cut, no reporter narration**

A suspected suicide bomb attack strikes Karachi, Pakistan's biggest city, killing at least four and wounded around 13 others.

The incident took place in the Malir area of the city, when an explosives laden motorcycle blew up near an armoured police vehicle.

The attack, targeting police, was the second since Thursday morning when unidentified gunmen opened fire on a police vehicle, killing three officers.