The U.S. Coast Guard said it found hundreds of dead sharks, likely caught for their fins, in an illegal net off the coast of Texas.

The so-called gill net stretched for five miles and contained 345 shark carcasses: 225 black tip, 109 bonnet and 11 bull sharks, the coast guard said in a news release Wednesday.

Gill nets, which are illegal in Texas and some other U.S. states, "indiscriminately kill any fish or marine mammal it snares across miles of ocean, often leaving much of the catch spoiled by the time it is hauled in," coast guard spokesman Cmdr. Daniel Deptula said.

The coast guard suspects this catch was to be harvested for fins and the rest of the animals' bodies discarded.

A surge in demand for shark fins, mostly for soup in Asia and Asian communities elsewhere, has threatened various species of the predators.

Canada outlawed "shark finning" in domestic waters in 1994, the U.S. in 2009, but sales continue.

Earlier this month, an Ontario judge struck down Toronto's ban on the possession, sale and consumption of shark fins in that city. It remains to be seen what will become of the ban passed by several other Ontario cities, including Newmarket, Mississauga, Oakville, Brantford and London. Calgary is set to vote on a city-wide ban on shark fins in January.

In November, the European parliament backed a blanket ban on shark finning, in which the fins are sliced off sharks, often while they are alive, and their carcasses dumped in the sea.