The captain of the Solong cargo ship who was arrested after crashing into an oil tanker off the English coast is a Russian national, the vessel’s owner said Wednesday, as maritime experts search for answers.

Stena was loaded with more than 200,000 tons of highly flammable jet fuel for US warplanes, while both vessels were powered by heavy fuel.

The captain of the cargo ship that crashed into an oil tanker anchored off the coast of Britian Monday has been arrested.

An oil tanker reportedly on fire in the North Sea after colliding with a cargo vessel. Lifeboats and a coastguard helicopter were called to the collision in the Humber Estuary on Monday morning, believed to involve a US-flagged tanker called the MV Stena Immaculate.

LONDON (Reuters) - Most of the jet fuel onboard the U.S.-flagged tanker Stena Immaculate that was hit by a container ship in a collision off Britain's coast remains contained and only two of the vessel's 18 fuel tanks have leaked, owner Stena Bulk said on Wednesday.

Fears of an environmental disaster eased on Wednesday, two days after a container ship ploughed into a stationary U.S. fuel tanker off northeast England, as the vessel's owner said the detained captain was a Russian national.