Egypt's state news agency is reporting that a naval patrol near one of the country's Mediterranean ports has come under attack from three boats, prompting an exchange of fire that wounded no sailors.

A military official told the MENA news agency that gunmen from boats fired at the naval patrol Wednesday north of the port of Damietta.

The official said air force and navy fighters were deployed to rescue the patrol after their boat caught fire. He said reinforcements "destroyed" the three attacking boats and 20 people were subsequently arrested. The official, unnamed in the report, did not identify the attackers.

Human smuggling is common in the Mediterranean. Troops increasingly have come under attack from militants since the ouster of Islamist President Mohammed Morsi last year, though never at sea.