The U.S. Border Patrol made the rare move of firing warning shots from a helicopter to stop a boat believed to be smuggling drugs off the San Diego coast.

The Border Patrol said in a statement Sunday that a Blackhawk helicopter and two of its boats were chasing down the panga boat Saturday night after it was spotted by the Coast Guard and men were seen dumping what appeared to be bales of marijuana overboard.

When the boat refused to yield, several shots were fired across its bow by the mounted guns on the Blackhawk. The three men aboard immediately stopped and the men were taken into custody.

Border Patrol officials say it's the first time they have used this tactic on the West Coast. They say strict protocols were followed to ensure public safety.