A Coast Guard crew patrolling in the Gulf of Mexico off South Padre Island has found an illegal net containing hundreds of dead sharks.

A Coast Guard statement Tuesday says the 5-mile-long gill net was found loaded with 345 dead sharks about 17miles north of the U.S.-Mexican border.

Gill nets are illegal throughout Texas, and Coast Guard Cmdr. Daniel Deptula described the nets as “wasteful.” He says such fishing methods already have depleted Mexican fisheries, causing fishing crews to move into U.S. waters in search of fish.

In 2012, the most recent year for which figures are available, Coast Guard Sector Corpus Christi has seized more than 49 miles of gill net.