ROQUE BLUFFS — Two women hikers who had been rescued after getting lost at Roque Bluffs State Park on Tuesday night drowned in their minivan a short while later, apparently after taking a wrong turn while trying to leave the park and driving off a boat ramp into the ocean.

One of the women was pregnant.

Their vehicle was found under water Tuesday night, about 175 feet off the Pond Cove boat ramp. Rescuers located it when they saw bubbles rising to the surface of the water.

Inside were the bodies of Amy Stiner, 37, who had lived in Machias for just a year, and Melissa Moyer, 38, of Sunbury, Pa., who was visiting Stiner on Tuesday night. Stiner was five months pregnant.

The accident occurred shortly after Stiner and Moyer were rescued when they got lost at the nearby Roque Bluffs State Park amid fog and a steady downpour. The two had called for help while hiking because it was getting dark and they couldn’t find their way back to their car.

An off-duty firefighter, who also works for the volunteer search organization Sunrise Search and Rescue, arrived in his all-terrain vehicle and found the pair on the western shore of the park. He took them and a dog belonging to one of the women to a nearby house, where a game warden picked them up and brought them back to their vehicle, a 2001 blue Dodge minivan, said Washington County Sheriff Donnie Smith.

But as the pair left the parking area, Stiner took a right on Schoppee Point Road instead of a left, which would have taken them back to Machias.

“The end of the road becomes the boat landing and they just weren’t familiar with it,” Smith said. “It was foggy and rainy and they literally drove off the boat landing right into the water.

“It’s just so easy to do. When I got the call last night, I knew what had happened,” he said.

The road ends in a remote boat landing about a mile away from the main parking area for the park. There is a sign near the ramp saying the pavement ends, but it is partially obscured by branches. There are no homes or businesses in the area, and none of the fishing boats were occupied, Smith said.

“It’s pitch black — dark as a pocket and there’d be nobody there at that time of night and in that weather,” Smith said.

The women were able to call 911 on a cellphone at 9 p.m., reaching the Maine State Police barracks in Orono.

“They said they were in the water and the car was filling with the water. And then the phone just went dead,” Smith said.

A game warden used the GPS coordinates from the cellphone to locate the general area where the van was located, off the Pond Cove boat ramp, but couldn’t find the vehicle right away. Members of the Washington County Sheriff’s Department, Machias Police Department, Maine Marine Patrol and U.S. Coast Guard joined the search.

One of the searchers then spotted bubbles rising in the water about 175 feet from shore. Travis Preston, a volunteer firefighter with the Jonesboro Fire Department and a certified scuba diver, dove down to the van, which had sunk in more than 20 feet of water, and discovered the bodies still inside.

It was 10 p.m., about an hour after the initial call.

The women were found in the back seat, probably because the van would have sunk front-end first, and the back would have been the last area to fill with water, Smith said. The dog, a pit bull mix, also died.

Smith said it’s possible the van’s electric windows and automatic door locks stopped working once the minivan was submerged.

Smith said other people have accidentally driven into the ocean at that spot, although never with such tragic results. In those cases, the cars floated for a period of time before sinking, which could explain why the van was found so far from shore, he said. Also, the tide was coming in fast — low tide was at 6 p.m. — which would have increased the distance from shore to the van.

The van was hauled out of the water using a cable and a winch. A representative of the Office of the State Medical Examiner was called to confirm the cause of death. Smith said blood tests will be conducted on the bodies, as required in any serious car crash, but he did not suspect alcohol or drugs contributed to the crash.

Stiner, who was originally from Pennsylvania, may have been unfamiliar with the Roque Bluffs area, Smith said. She and her husband, Gregg, were organic farmers. There was no phone number listed for Amy or Gregg Stiner in the Machias area.

Moyer worked as a teacher’s aide in the local school district in Pennsylvania. Smith said Moyer’s immediate family members — her Facebook page indicates she has a son — were headed to Maine on Wednesday.

Other members of Moyer’s family in Pennsylvania declined to comment when reached by telephone.

Smith said it’s not clear exactly why the pair turned the wrong way on Schoppee Point Road.

“This lady lived on Kennebec Road. She wasn’t far from home,” Smith said. “I suspect they were cold and wet and just made a mistake.”

David Hench can be contacted at 6327 or at:

[email protected]

Correction: This story was updated at 3 p.m., July 24, 2013, to state that Amy Stiner of Machias was five months pregnant, and not Melissa Moyer. A previous version of this story had incorrect information supplied by authorities.