Captured American in Nigeria released

LAGOS, Nigeria (CNN) - An American oil worker who was abducted Thursday from an oil field in Nigeria was released a few hours later.

"Captain J. Stone who was captured by our fighters in the early hours of today was released unconditionally to his employers by 16:45," (11:45 a.m. ET) said a statement signed by a representative of the Movement for the Emancipation of the Niger Delta, or MEND.

The report was confirmed by a spokesman for Chevron Corp., who said Stone was released to Nigerian authorities, and that he was working for Tidewater Marine Services on contract to Chevron Nigeria Ltd. A spokeswoman for Tidewater said no one was immediately available to comment.

–CNN's Christian Purefoy contributed to this report.