A large blast near the southern port city of Dailam in Iran was the result of "geophysical exploration" in the oil-rich area, a local official in the Bushehr province said

A large blast near the southern port city of Dailam in Iran was the result of "geophysical exploration" in the oil-rich area, a local official in the Bushehr province said. No casualties were reported in connection with Wednesday's explosion, which some witnesses attributed to a missile dropped from a plane, according to early reports on Iranian state television. State television later said the blast could have come from a fuel tank that fell off an airplane. The official in Bushehr province said the explosion was connected to "geophysical exploration" in the region, which sees frequent oil exploration. Other Iranian officials said there is also heavy air traffic in the region. A reconnaissance team is on its way to the site to investigate, officials said. Ali Agha Mohammadi, the head of the security commission in Iran's National Security Council, said the explosion was not the result of a missile attack, as some witnesses had claimed. Iran has a Russian-built nuclear plant in the Bushehr province, in which Dailam is located.