Timergarah (Pakistan), Feb 3 (IANS) Three foreign journalists were killed and 16 students injured when militants detonated a bomb near a girls' school here in northwest Pakistan, media reports said Wednesday.

The blast took place near the Koto Girls School in Timergarah area in Lower Dir district.

Militants targeted the journalists' security convoy, police said.

At least 15 girls were trapped inside the school building after the blast, district police officer (DPO) Mumtaz Zarin told Dawn news.

'It was an IED (improvised explosive device) blast,' he said.