A portion of the busy Houston Ship Channel was shut Monday after two 600-foot ships collided in fog, causing a leak of flammable liquid.

Methyl tertiary-butyl ether, or MTBE, a gasoline additive aboard the Danish-flagged chemical tanker Carla Maersk, leaked from tanks that ruptured in the vessel’s collision with a 623-foot Liberian bulk carrier, Conti Peridot, Coast Guard Petty Officer Manda Emery said.

It was the second ship collision in the channel in less than a week. No pollution and no injuries were reported last Thursday when a 445-foot tanker and 892-foot container ship bumped about 15 miles up the channel from Galveston.

More at the Associated Press