UPDATE: Driver attempted illegal U-turn on Route 80, source says

The approximately 44-mile drive from East Brook Middle School in Paramus to Waterloo Village should make for a simple ride - no long, winding trek along the state's backroads or navigating jammed city blocks.

Online directions advise visitors to travel Route 80 before taking Exit 25 toward Stanhope. A couple more turns before a driver reaches the historic canal site.

As investigators probe what caused a deadly wreck Thursday morning involving a Paramus school bus one central question has emerged: Why was the bus -- one of three shuttling 38 fifth-graders and six chaperones -- past the Route 80 exit for Waterloo when it crashed?

Did the driver miss the exit that the two other buses seem likely to have taken, given the fact that they reached Waterloo Village?

The wreck occurred near a break in the Route 80 median, which is closed to all but authorized vehicles. A "No Turns" sign is posted near the paved area between an opening in two metal guardrails.

Authorities would not say if they believe the driver was attempting to make an illegal turn on the highway before the crash. But, citing multiple sources, NBC reported that footage from state Department of Transportation traffic cameras show just that, an ill-fated U-turn attempt after the bus driver missed Exit 25.

The next exit would not be until Exit 19, about six miles further down the highway.

A State Police spokesman said investigators were working to vet a range of reports, including claims gathered from social media, to determine the chain of events that ended with a fifth-grader and teacher dead.

Forty-three others were hurt and taken to area hospitals for a range of injuries, including some reported as in critical condition.

A preliminary report released by police raises more questions on how the crash occurred than it answered.

"[The bus] entered westbound Interstate 80 from southbound U.S. Highway 206," according to that account. "In the area of milepost 25.1, the school bus and a Kenworth dump truck collided, which caused the bus to overturn."

One student, speaking outside Morristown Medical Center, described a truck hitting from behind before the bus flipped.

It seems unlikely, however, that the bus pulled onto Route 80 from 206. If it had, the accident would have had to have occurred before the end of the on-ramp for the bus to crash where it did.

Noah Cohen may be reached at ncohen@njadvancemedia.com. Follow him on Twitter @noahyc. Find NJ.com on Facebook.