It was only a drill when the tactical response team swarmed the Martha’s Vineyard Regional High School campus Thursday morning.

A Martha’s Vineyard Tactical Response Team training exercise Thursday at the Edgartown Cinema offered both a somber reminder of recent terrorism and a reassuring sense that Island law enforcement is as prepared as possible for such events.

Police knew it was a drill. But when a 911 call reporting an active shooter inside the Edgartown School came in Saturday morning, the response was just like the real thing.

The Martha’s Vineyard Tactical Response team, a highly trained group of police officers, was created to quickly respond to emergencies on a geographically isolated Island. But last week the team was called to join officers from around the state in a large manhunt for one of the suspects in the Boston marathon bombing.

Friday’s massive manhunt in Watertown for Boston marathon bombings suspect included members of the Martha’s Vineyard Tactical Response team.

Edgartown police chief Antone Bettencourt said Monday that the Island team, a highly-skilled group of officers from most Island police departments, was called to Boston last Friday to assist with a search for Dzhokhar Tsarnaev.