Wire and local reports say a well in the Russian Arctic gushed for nearly two days before being brought under control on Sunday morning.
Reports from the Associated Press and Agence France Press estimated the spill at the Trebs field in the Nenets region at 2000 tonnes, roughly 14,000
barrels. The release affected an area of up to 8000 square metres, the reports said.
Russian news service RIA Novosti, quoting a regional official, reported the spill started at around 5:30 pm Moscow time on Friday.
It was brought under control by early Sunday morning, no injuries were reported and the wellhead did not catch fire, RIA Novosti said.
The license for the field is held by Bashneft-Polyus, a joint venture between regional producer Bashneft, with a 75% stake, and Lukoil, with a 25% stake.
Control of that license remains in question, however, given an ongoing Moscow dispute over the terms of the lease.
The joint-venture deal for the two fields was initially set in April 2011, which are estimated to have recoverable reserves of 1 billion barrels.
A report from the Moscow Times said the well at times was spewing oil as high as 25 metres into the air, quoting a regional official who surmised human error played a role.
The well likely blew out when an worker tried to operate an old wellhead only to find out too late that its plug had corroded, AFP quoted a regional official as saying.