An NBC employee who was working along the lakefront helped rescue a man who jumped into the water early Sunday on the North Side.

David Marshall was at North Avenue Beach about 3:50 a.m. shooting pictures of icy waters when he saw a man thought to be in his 40s or 50s walk by wearing “nothing but a t-shirt.”

“He was talking to himself and I asked if he is OK,” Marshall told reporters at the scene. “He just gives us a blank stare.”

Marshall said the man eventually made some sort of statement, faced the lake and jumped in.

Once he jumped in, Marshall informed his coworkers and threw a rope to the man, who held on to it and stayed above water until rescue workers arrived.

The Chicago Fire Department and city’s Marine Unit soon responded pulled the man out of the water, authorities said.

Marshall said his coworkers became concerned for the man and called police before he jumped into the water.

The man was taken to Northwestern Memorial Hospital where his condition had stabilized.