A van driven by a Story County resident accompanied by his wife crashed into the lake at the Ada Hayden Heritage Park just before noon Sunday.

According to an Ames Police Department press release, the van was westbound on Riverside Road approaching Highway 69 when the accident occurred at approximately 11:55 a.m. The driver experienced an unknown medical condition during the accident and was transported by ambulance to the Mary Greeley Medical Center.

The identity and condition of the couple was unable to be disclosed.

Brian Thompson, 43, of Ames, was driving back from a 3-D archery shoot with his wife and a friend when he saw the accident in his rearview mirror. He turned around to assist.

“The decision to help wasn’t too hard to make,” Thompson said. “I was just thinking about how beautiful and blue the lake was when I saw the van go screaming through the intersection in my rearview mirror. When I got there the lady in the passenger seat was pretty frantic.”

Thompson said the man in the driver seat was unresponsive and shaky when he and other witnesses tried to help get him out of the van. They were unable to open the door, so Thompson went to the passenger side to help the woman. The woman was able to get to shore before the van went underwater but was unable to help the man get out.

“He must have been under for three to four minutes when he came up,” Thompson said. “He was face down and unconscious when we got him to shore and the paramedics began giving CPR right away.”

Lynn Swett, 41, of Story City, was on his way to a movie with his kids when he stopped to assist the couple.

“The van was a long way out,” Swett said. “When the van went under I went underwater with him but lost him until he came up again. We about killed ourselves trying to get them out.”

A third passerby, John Kazwell of Ames, stopped to help save the motorist and his wife. Kazwell was unable to be reached for comment.

Central Iowa Underwater Search and Rescue responded to the emergency and sent a dive team to the lake.

“[The dive team] will check out the vehicle to make sure no one else is in it,” said George McConeghy, president of Central Iowa Underwater Search and Rescue.

The dive team also attached a tow cable to the van, which allowed it to be pulled out of the lake. The van was pulled onto the shore at approximately 3 p.m.