BLACK RIVER FALLS, Wis. (AP) -- A man whose semitrailer truck plunged off Interstate 94 into the Black River, killing him and his 7-year-old son, probably fell asleep at the wheel, the Black River Falls fire chief said Tuesday.
The accident happened at about 5:50 a.m. Monday, and the Jackson County dive team recovered the man's body later in the morning from the truck's cab in about 25 feet of water, police and Fire Chief Steve Schreiber said.
Police identified the victims as Robert J. Marks Sr., 36, of Milwaukee, and his son, Robert J. Marks Jr.
The westbound truck went into a median strip for about 200 feet and crashed through a guard rail between the eastbound and westbound bridges before falling into the river, police said.
``My theory is he probably fell asleep and thought he could straighten it out,'' Schreiber said. ``He tried to drive out of it and ended up in the river.''
Schreiber said emergency responders did not know the child was in the cab until they eventually pulled it from the water later Monday.
``When we started bringing the cab out of the water, we knew we had a second victim,'' the chief said.
