Fourteen people have been killed in a violent clash between two gangs in the Pakistan city of Karachi.

Senior police official Faisal Bashir said: "The clash erupted this morning when two gangs exchanged heavy gunfire. 

"Later, they fired RPGs and lobbed hand grenades at each other."

He said that 39 people, including 15 schoolchildren, were injured.

Mr Bashir said the violence had erupted after one of the gangs had kidnapped a member of the other gang the night before.

The attack took place in Lyari, one of the poorest and most violent neighbourhoods of Karachi, where clashes between rival gangs linked to political and ethnic groups erupt continuously.

Karachi, a city of 18 million people that contributes 42% of Pakistan's GDP, has been plagued by sectarian, ethnic and political violence for years.