The driver of a Toronto-bound double-decker that rammed into a low-hanging bridge took a wrong turn that turned deadly, police said Sunday, but why he failed to see warning signs remains a mystery.
Four people were killed in Saturday's accident.
Many others on the bus, including several Canadians, were injured after the towering Megabus from Philadelphia failed to clear a low-hanging railway bridge, flipped onto its side and smashed into a concrete support at the side of the road.
Onondaga Sheriff Kevin Walsh said the coach was scheduled to stop at a bus station in Syracuse, but the driver took the wrong turn after exiting a highway and didn't seem to notice flashing signs warning against the low bridge.
"Why he missed those signs, why he didn't see the bridge, those are things that are still unanswered," Mr. Walsh said.
The Megabus had 28 passengers aboard, including seven Canadians, when it crashed around 2:30 a.m. on the Onandaga Lake Parkway – a route the bus wasn't supposed to be on – in a suburb of Syracuse, some 400 kilometres southeast of Toronto.
All Canadians on board escaped major injury, but five people remain in Syracuse hospitals. One is in critical condition, while four others, including the driver, are in serious condition.
Megabus and the Onondaga County Police are probing the cause of the crash with two separate investigations.
Police and the bus company have been able to question driver John Tomaszewski and have determined he was not intoxicated, but are still looking for more information.
The 59-year-old driver from New Jersey had made the Philadelphia-to-Toronto run several times before.
"He had a very severe head injury so he's confused," said Mr. Walsh. "He's been co-operative, and as of last night he still didn't know how he ended up where he was."
Police have taken statements from the passengers and will later conduct a full accident reconstruction to determine factors in the crash.
"At this point we just don't know until we've got all the facts together," said Mr. Walsh.
The case will later be taken to a district attorney who will make a decision on whether the case should go to a grand jury.
"There have been a lot of accidents along that stretch of road," said Mr. Walsh. "I believe this is the first fatal accident that had anything to do with the height of the bridge."
Don Carmichael, senior vice-president for Coach USA, which operates Megabus, says the driver "obviously made a wrong turn" because he wasn't on the trip's prescribed route.
He wouldn't elaborate on the company's crash investigation saying the company was still dealing with "very much a fluid situation."
Police identified three of the dead as Kevin Coffey, 19, of Kansas, Ashwani Mehta, 34, of India, and Benjamin Okorie, 35, of Malaysia.
The fourth victim is thought to be an 18-year-old from New Jersey, but police aren't releasing her name until she has been identified by her parents.
All four were sitting near the front on the upper tier of the bus.
Survivors described a terrific jolt as the top of the bus was ripped back "just like an accordion" after the crash.
Many of the 20 passengers who were released from hospital have been transported home or to destinations of their choice.
The 13-foot-tall double-decker struck the bridge span between two large signs warning that the clearance was 10 feet, 9 inches.