Two lost hikers who had just been rescued during a driving rainstorm in a Maine state park died after they took a wrong turn and drove their van into the Atlantic Ocean, authorities said Wednesday.

Lt. Travis Willey / Washington County Sheriff's Department via AP Rescue diver Travis Preston, a Jonesboro, Maine, firefighter, hooks up a minivan in the water on the boat ramp at the scene of a double fatal accident Tuesday evening July 23, 2013, in Roque Bluffs, Maine.

The women — identified as Amy Stiner of Machias, Maine, who was five months pregnant, and Melissa Moyer of Sunbury, Pa. — were found dead in the back of the van about 175 feet from shore in Pond Cove near Roque Bluffs State Park on Tuesday night, the Washington County Sheriff's Department said.

Their dog was also dead, the sheriff's department said.

According to the sheriff's report, the women got lost while hiking in the park about 9 p.m. ET in heavy wind and rain. A member of a local search rescue service found the women and their dog, and state wildlife wardens drove them back to their van.

About an hour later, the Warden Service got a call that the women had driven their car into the water about a mile from where they had last been seen, the sheriff's report said.

The Portland Press-Herald reported that the call came from the women themselves, who managed to report that the van was filling with water before their cellphone went dead.

Search teams found the van underwater about 175 feet off a boat ramp at Pond Cove.

"The end of the road becomes the boat landing, and they just weren't familiar with it," Sheriff Donnie Smith told the Press-Herald. "It was foggy and rainy, and they literally drove off the boat landing right into the water."

Smith told the newspaper that the van likely was found so far from shore because it floated for a while before sinking. The women were in the back seat because the front of the van would have sunk first and the women would have retreated to the back, he said.

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