Kuwait's state-run oil company says it has contained an oil spill at a drilling rig in the small, crude-rich country.

A statement issued on Wednesday by the Kuwait Oil Co. says there would be an investigation into the cause of the spill, which happened Tuesday at its BWD-133 drilling rig at the Ahmadi field.

The statement did not say how many gallons of oil were spilled in the onshore leak. A company spokesman did not respond to a request for comment.

In February, a fire erupted at an oil well in northern Kuwait after an oil spill.

OPEC member Kuwait is a major oil producer. The U.S. Energy Information Administration says Kuwait produces some 2.8 million barrels of crude oil a day and holds the world's sixth-largest oil reserves.