SOUTH PADRE ISLAND – Test results show dozens of sea turtles found dead last month may have drowned, according to Sea Turtle, Inc. Tests also confirmed illegal fishing may be to blame.

Threatened sea turtles are getting caught and killed. The Coast Guard says they haven’t seen these cases in a long time. They say the problem is coming from across the border.

The struggle to protect U.S. waters and stop fisherman who continue to exploit sea life.

Fisherman using illegal forms of fishing, such as long lines of gillnets, are just too effective, the Coast Guard says.

The Coast Guard are up against lanchas, boats from Mexico built for speed and endurance.

Watch the video above for the full report.