Bomb blast near BA office in Iran

British interests in Iran have been targeted in the past

A small bomb has exploded at a building which houses the offices of British Airways and the BP oil firm in the Iranian capital, Tehran.

A British Embassy spokesman said the bomb went off on the 10th floor of the block at about 0445 GMT.

It exploded in a dustbin outside the BA office, causing limited damage but no casualties.

In 2003, security was tightened at the British Embassy in Tehran after it was targeted twice by unknown attackers.

UK targets

"A small parcel device exploded (...) outside the BA and BP offices on the 10th floor of Sayeh building. There were no casualties," the spokesman told news agency AFP.

The glass in front of the BA office was shattered and the emergency door damaged, but the inside of the office was not damaged.

One Iranian news agency said it may have been a stun grenade which exploded, reports the BBC's Frances Harrison in Tehran.

Iranian interior ministry spokesman Jahanbaksh Khanjani said it was not clear yet what caused the blast and police were still investigating.

The security forces sealed off the building and staff were evacuated to a nearby park.

In 2003, the British Embassy was targeted by gunmen in September and a fire bomb in November, causing damage but no casualties.