The owner of a tugboat that collided with a ship last month, dumping nearly 170,000 gallons of oil into the Houston Ship Channel, claims in court filings the ship was speeding and being operated in a reckless manner.

In court documents filed earlier this month, Houston-based Kirby Inland Marine alleges the March 22 collision was caused by gross negligence on the part of Sea Galaxy Marine, the ship's owner based in Liberia in West Africa.

In its own court filings, Sea Galaxy says the collision was not its fault.

A Kirby Inland spokesman and a Sea Galaxy attorney both declined comment because of the ongoing investigation.

The U.S. Coast Guard, which is still investigating the accident's cause, didn't immediately return a phone call seeking comment.