BAYOU LA BATRE, Ala. — Authorities searched Wednesday for the bodies of four children believed to have been thrown off a bridge by their father.

Lam Luong, 37, of Irvington confessed Tuesday night to driving to the Dauphin Island bridge, stopping and tossing the youngsters off the span, which is as high as 80 feet above the water in places, Detective Scott Riva said. Luong faced charges of four counts of capital murder and was due in court Wednesday, Riva said.

Missing and presumed dead were 4-month-old Danny Luong; 1-year-old Lindsey Luong; 2-year-old Hannah Luong; and 3-year-old Ryan Phan. Phan is not the man's biological child, but Luong raised him from infancy, authorities said.

At least three boats were being used in the search, and the Coast Guard was sending another boat and a helicopter, Riva said.

"It's been a nightmare," said Riva.

Luong is jailed in Mobile, and Riva said he did not know whether he had a lawyer. There was no telephone listing for Luong.

Police Chief John Joyner said the act appeared to be an act of revenge aimed at Luoung's wife, the Press-Register of Mobile reported. Police said Luong reported the children missing Monday. He reportedly told authorities that a woman who had the children failed to return them to him.

The Dauphin Island bridge connects coastal Alabama to a barrier island located about three miles south of Mobile Bay in the Gulf of Mexico.