Massive explosions rocked a major US military base outside the northern Iraqi city of Kirkuk tonight, shrouding the city in smoke.
Police said the explosions were caused by a rocket strike on an arms store.
There were no reports of casualties.
Shells and rockets screamed into the night sky over the base at Kirkuk's main airport and thick smoke rolled across the whole area.
Loudspeaker announcements could be heard on the base warning troops to stay under cover.
US military spokesmen in Baghdad said they were unaware of the incident. US officials in Kirkuk could not be reached.
"A Katyusha rocket hit an arms store," district police chief Borhan Taeb Taheb said.
He said he knew of no casualties among civilians outside the base, which covers a very wide area. No ambulances or fire trucks were seen moving in the city, which was under curfew.
Kirkuk, 250 km (155 miles) north of Baghdad, is the industrial hub of Iraq's vital northern oilfields. There has been considerable violence there in recent months, notably between rival communities of Arabs, Kurds and Turkmen.