Two men caught off guard by the incoming tide over a sandbar offshore from Hills Beach in Biddeford had to be rescued Saturday afternoon, but one was unresponsive when he was brought ashore.

About 3:15 p.m., people on the beach heard the men yell for help and could see their heads above water, witnesses said.

Keith McManus of Barrington, Rhode Island, said by the time he began motoring out to the men in his inflatable boat, he could see only one head above water.

McManus said one man was struggling to keep the second man above water and the second man was unconscious by the time they got him aboard the boat.

Another rescuer on a jet-powered personal watercraft then towed the boat back to the beach, where two others on the beach began performing CPR on the unresponsive man, he said.

“By the time the emergency personnel got to him, I thought he was gone. Then they brought him back,” McManus said.

Lt. Eric Wheeler of the Biddeford Fire Department said that when his fire and EMT crews arrived, they treated the man and then put him on an ambulance to Southern Maine Health Care in Biddeford. The man was admitted to the hospital in serious condition, Wheeler said.

The man was transferred to Maine Medical Center in Portland early Saturday evening.

The other man who had been in the water was unharmed, Wheeler said.

The two men were in their early 30s or early 40s, Wheeler said, but their identities were not immediately released.

McManus said the men were out about 200 yards on the sandbar that connects to Basket Island at low tide.

Staff Photographer Derek Davis contributed to this story.