An ambulance that rushed a dying Chicago Marathon runner from the race to the hospital apparently got lost on the way, authorities said.

Chad Schieber, a Midland, Mich., police officer and father of three, collapsed while running the Oct. 7 race. An autopsy blamed his death on a heart condition called mitral valve prolapse, though heart experts say the condition rarely is dangerous.

Schieber, 35, was transported in an ambulance from Niles, which was one of 30 suburban crews called to help when high temperatures sent hundreds of runners to hospitals.

The crew called Chicago dispatchers to report Schieber was in full cardiac arrest, and they planned to take him to the University of Illinois at Chicago Medical Center, Chicago Fire Department spokesman Larry Langford said this week, but there's no record of them seeking directions.

Niles Fire Chief Barry Mueller, however, said the crew did ask radio dispatchers for directions but got no response.

"That's not unusual. The airwaves could be jammed," Mueller said.

Mueller said the ambulance crew drove a couple blocks in the wrong direction when they flagged down a city ambulance and got directions. But the crew then apparently drove by the UIC Medical Center because they couldn't find the emergency room entrance.

The ambulance ended up a few blocks away when crew members saw the ER sign for the West Side Veterans Administration Hospital. The hospital is not part of Chicago's emergency response network but has a fully working ER, officials said.

Langford and Mueller could not say how long it took to transport Schieber to the hospital or whether it would have helped to get him there sooner.