An earlier version of this story contained an error. Only Arnold Bradford Williams was seen throwing beer cans from the overpass, according to the report. We regret the error.

North Charleston investigators said they uncovered information Tuesday that prompted them to pursue a charge of reckless homicide instead of drunken driving against a trucker in a fatal pileup on Interstate 526.

But officials have not specified exactly what led to the adjustment after suspicion was raised when witnesses saw Arnold Bradford Williams “remove a pack of alcoholic beverages out of the cab of the truck then willfully toss them over the side of the interstate right after the collision occurred” Monday, according to an incident report.

The report hinted at an investigation at a hospital, indicating that Williams underwent sobriety testing. But authorities would not discuss any results.

The North Charleston Police Department released the report Wednesday, but it revealed little new information regarding the wreck at the Rivers Avenue overpass and the allegations against the 35-year-old from Latta.

But it confirmed some of the details reported by witnesses of the crash that killed Lauren Elyse Baccari, 27, a student who was scheduled to graduate this spring from the Medical University of South Carolina.

The report stated that Baccari's 2005 Acura was stopped in a traffic jam caused by a crash 2 miles down the road. The police said Williams was driving recklessly by going too fast, considering other traffic wasn't moving at all.

About noon, his truck slammed into Baccari's car, causing a chain reaction that involved another tractor-trailer and three other smaller vehicles.

Traffic officers quickly learned of the account that Williams had been throwing beer cans from the overpass, according to the report. They gathered the discarded items.

That moved the police to send an investigator to Trident Medical Center, where paramedics had taken Williams for treatment. He was not seriously hurt.

After an investigation at the hospital, the police spoke with prosecutors and decided on the charge of felony driving under the influence with death. Williams was jailed on the count about five hours after the crash. His eyes appeared red in his booking photograph.

But the next day, the report stated, investigators obtained “additional information” and once again spoke with police supervisors and authorities from the 9th Circuit Solicitor's Office.

That's when the count was adjusted to reckless homicide. It carries a maximum of 10 years behind bars, while the charge of felony DUI with death would have brought between one and 25 years in prison.

Police officials would not discuss what might have led Williams to toss out the cans, but state law has little tolerance for alcohol use among commercial drivers.

A truck driver's blood-alcohol concentration must stay below 0.04 percent. For non-commercial drivers, the limit is 0.08.

Commercial drivers with even a trace of alcohol in their system are taken out of service for 24 hours. And when alcohol consumption is suspected, testing is mandatory.

Williams did not have previous arrests in South Carolina, according to the State Law Enforcement Division. Court records show that he has at least one ticket for having an open container of alcohol inside his vehicle. During a bond hearing, a magistrate also mentioned his “history of speeding.”

Family members said Williams supported his family in Dillon County by driving a truck in the Lowcountry.

Baccari was in her fourth year at MUSC, according to a classmate. She was born in Pennsylvania and raised in Little River near North Myrtle Beach. She completed her undergraduate studies at the College of Charleston, and enjoyed gardening, cooking and playing with her pit bull.

The classmate, who asked not to be identified, said Baccari was eager to hear in March where she would be sent for residency training. She had dreamed of practicing family medicine somewhere in rural South Carolina.