NEW ORLEANS – The search for a man who went missing in Lake Pontchartrain Wednesday resumed Thursday morning.

An eyewitness told WWL-TV that a man was in a canoe or kayak that began to take on water after it was hit by a wave around 2:30 p.m. Wednesday. The witness said the man went under about 50 yards off the shore.

The Coast Guard later said the man was on a 14-foot flat-boat that capsized.

Onlookers who saw the man struggle to stay above water tried to get to him but were not able to before he disappeared below the surface.

The Coast Guard has not identified the man. They were joined by multiple agencies including New Orleans Police Search and Rescue and New Orleans Fire Department as they combed the choppy lake waters.

Boats armed with sonar and drag lines hoping to get a ping on the possibly sunken vessel so far have turned up empty.

An NOPD spokewoman said Thursday morning the department has received no missing-person reports for anyone who matches that description who may have been on the lake Wednesday.