Alaska Department of Public Safety on Thursday identified the four men killed when a small plane crashed in shallow waters near a remote coastal town. This was reported by Qazaqyia.kz citing Associated Press.

The pilot was identified as Eric Middlebrook, 68, of Anchorage. The passengers were Ronald Schmidt, 65, Lance Schmidt, 20, and Daniel Simons, 82, all from California.

The Piper PA-24 was headed Wednesday for the airport in the small town of Seldovia after taking off from Anchorage when it crashed. Seldovia's airport is about 135 miles (220 kilometers) southwest of Anchorage.

After the crash, the plane came to rest in about 15 feet (4.6 meters) of water in the Seldovia Slough near the shore. Troopers had to wait for the tide to go out before they could reach the plane and remove the victims.

It was not immediately clear what caused the crash. U.S. Sen. Dan Sullivan, of Alaska, said he was awaiting a briefing from the NTSB and Federal Aviation Administration as they work to determine what went wrong.

"These tragedies are heartbreaking and unacceptable, which is why aviation safety and infrastructure in Alaska continue to be a top focus of mine," he said in a social media post.

Less than a week earlier, another plane crashed at a remote military site in western Alaska, killing all eight people aboard. The aircraft had been making its second approach to the runway in heavy fog and its pilots could not see the gravel airstrip, authorities said.