Three people escaped safely from the Menemsha channel Tuesday evening after the car they were driving went off the pier near the Coast Guard boathouse and sank in the harbor.

Chilmark police identified the driver as Robert Drew of Andover. One passenger was transported to the hospital for evaluation, police said.

According to a preliminary police report, Mr. Drew was attempting to turn around near the Coast Guard boathouse lot. The vehicle, a 2016 Land Rover LR4, has a remote dial gear-shifter, the report said. The driver thought he had turned the dial to the reverse position and pressed the accelerator to begin backing up, according to the report.

“As he pressed the accelerator, Drew stated the car began to roll forward so he gave it more gas,” the report said. “Consequently the Land Rover [drove] off the pier into the water.”

The vehicle broke through the guard rails and landed in the channel, and then began sinking slowly while turning over, according to police.

The driver was able to escape from the driver’s side window, according to the report. The passenger in the front seat was able to escape by opening the door. The driver helped rescue the passenger in the back seat through an open window.

Bystanders assisted from both boat and shore, with one unidentified bystander diving into the water, police said.

“I don’t know how they did it, the tide was ripping,” Chilmark fire chief Jeremy Bradshaw said from the pier Wednesday morning. “It was really heroic.”

According to Chief Bradshaw, the passengers drifted out with the tide and were able to climb onto the floating dock below the pier.

He said the fire department and state environmental police arrived on scene later to ensure there were no leaking fluids or fire hazards. The vehicle remained in the channel overnight, submerged in about seven feet of water with headlights still on, police said. The Menemsha harbor master marked the vehicle with a hazard light overnight.

At low tide on Wednesday morning, the car was pulled from the channel by John Keene of Keene Excavation, before a crowd of onlookers.

Two divers from the Chilmark fire department and Vineyard Scuba assisted. The vehicle was lifted from the channel, water pouring from the broken windows and seaweed hanging from the undercarriage, and lowered onto the pier.

“It was full of water and a couple of crabs,” Chief Bradshaw said. “We’re just glad everyone was safe.”

Mr. Drew was cited for failure to use care in stopping, backing and turning, according the police report. Police also said they are working to identify and thank the bystanders who assisted during thee incident.