A Sea Shepherd vessel has been damaged during an aggressive altercation off the coast of Panama.
Video footage shows the John Paul DeJoria surrounded by five boats they were monitoring for illegal long-line fishing.
Objects are then hurled at the activists, before one of the vessel rams the Sea Shepherd boat.
The incident lasted more than an hour, with the crew claiming they didn't provoke the situation. It ended when Sea Shepherd fled.
"Sea Shepherd crews are not intimidated by intimidation, threats of violence and assaults," said the group's president, Capt Paul Watson.
"I am proud of the crew of the John Paul DeJoria for standing strong in the face of these poachers in their defense of the Coiba Island marine reserve.
Sea Shepherd says the John Paul DeJoria suffered minor damage.
"It's high time the Panamanian authorities made this incredibly important marine area a reserve not only by name but also in practice," said John Paul DeJoria Capt Jessie Treverton.
"This area needs to be a zero take zone and properly policed. Sea Shepherd is offering to provide the M/V John Paul Dejoria, resources, and crew to assist the rangers in their important work."