Authorities say the search for two teenage boys who went missing while swimming in Lake Michigan has become a recovery effort.

Authorities who gathered at Holland State Park say four teenage boys were swimming Wednesday when they were pulled out by strong currents and high waves around 7:30 p.m. They say two boys managed to get out of the water, and boats and helicopters were used to try to rescue the others.

Before 11 p.m., authorities said the water was too rough and they temporarily halted the search. But the U.S. Coast Guard tells WOOD-TV its crews actively searched through the night. The Grand Rapids Press reports Ottawa County sheriff's divers are resuming the search Thursday.

The missing teens are 14 and 17 years old. Their identities haven't been released.