SAN DIEGO -- Coast Guard investigators have a key piece of evidence that may tell them why a fishing boat sank off San Diego's coast last week, 10News reported.

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MISSING FISHERMEN Search Called Off For Missing Fishermen

A portion of a fishing net from the Gina Lisa fishing boat was recovered by another fishing boat. It was turned over to Coast Guard investigators Tuesday morning.

Investigators will examine the net to see if the Gina Lisa may have been hit by a larger vessel.

The captain of the boat, Vito Romani, a long time Point Loma fisherman, and a crew member were lost at sea.

U.S. Coast Guard Chief Warrant Officer Mike McCright said, "The vessel is over 3,000 feet deep so it is almost impossible for us to get at. This is our best piece of evidence at the moment."

Investigators will look for breaks in the net, paint and any other evidence that could connect another vessel to the sinking of the Gina Lisa.

A memorial mass will be held Wednesday at 10 a.m. at Our Lady of Rosary Church in Little Italy for Romani and his shipmate.