A confrontation that took place on Chappaquiddick on Saturday is under investigation by Edgartown police as a possible crime.

Police chief Bruce McNamee said the incident occurred on Saturday when four occupants of a white Jeep reportedly harassed the passengers in an open air touring vehicle owned by the Trustees of Reservations. He said the jeep was believed to have been occupied by four white Florida men in their 40s and 50s, while the Trustees tour group that was visiting Cape Pogue and was all women of varying ethnicities, including Asian, African American and white.

Chief McNamee said the alleged harassment was first reported when a narrative of the incident and a photograph of the Jeep was posted on social media on Saturday. The post prompted calls for law enforcement intervention. Chief McNamee said the incident was not reported to the police until Sunday, and the delay has complicated the investigation.

“I wish that this could have been reported to us, and we could have acted in real time,” the chief said.

Chief McNamee said police have interviewed the tour driver and the driver of the Jeep.

“What we have determined so far is there was yelling from the gentlemen in the Jeep to the people on the tour bus: comments involving Mary Jo Kopechne as well as President Trump. That’s what we have so far,” Mr. McNamee said.

He said police traced the license plate number of the Jeep to a home in Oak Bluffs and found the driver there. The man was cooperative and was interviewed. He was not the owner of the vehicle. All four of the men in the Jeep were from Florida, and at least three had left Massachusetts since Saturday.

Trustees superintendent Chris Kennedy said the men would not be welcome on the property again.

“Their behavior could most generously be described as really obnoxious,” he said.

Chief McNamee confirmed that the oversand vehicle sticker had been removed from the Jeep.