A weak explosion occurred Tuesday near the offices of British Airways and British Petroleum in a building in the north of Tehran, but caused no casualties, witnesses said.

The blast occurred at 9.15 a.m. (0445 GMT) outside the BA and BP office in the Sayeh building, said a witness, adding there were no immediate reports of casualties, but some facilities of the building was damaged.

Iranian Interior Ministry confirmed the explosion, saying that they were not sure whether it was a bomb or a gas canister, which was subject to the investigation of the bomb disposal teams dispatched to the spot.

Later, a spokesman for the British Embassy said that the explosion device was placed in a dustbin outside the office, which caused limited damage and shattered window glass.

The incident came just one day after Iran takes substantial steps toward resumption of its uranium conversion activities and received hard warnings from the Europeans.

Tehran on Monday announced that the seals on the uranium conversion facility in the central city Isfahan would be removed and a letter had been submitted to the International Atomic Energy Agency to inform of the resumption.

Along with France and Germany, Britain is one of the brokers of the Iranian nuclear issue on behalf of the European Union.

Due to London's close alliance with the United States, the British Embassy in Tehran is the often target for Iranian extremists whenever there were fluctuations in the relations between Iran and the West.

Source: Xinhua