The 26-year-old off-duty traffic agent who crashed on the Williamsburg Bridge early Thursday morning, killing back-seat passenger Amanda Miner on her 21st birthday, was driving at nearly twice the speed limit just before impact, according to a criminal complaint released by the Manhattan DA's Office.

According to the NYPD, Stefan Hoyte lost control and struck a concrete barrier, then a bridge support column, around 3:15 a.m. on Thursday. He had reportedly been out celebrating Miner's birthday with another off-duty traffic agent. Hoyte and the other agent, identified by the Daily News as 24-year-old Michael Camacho, were treated for minor injuries at Bellevue Hospital.

The criminal complaint describes the scene of the crash in gruesome detail. Miner was "severed in half" on impact, according to a responding police officer; Hoyte's vehicle, a 2013 infinity G37, was also "severed in half horizontally."

Hoyte also allegedly admitted to police that he was the driver, and had been driving between 50 and 60 miles per hour just before the crash. He also said that he had been at a bar earlier that night, where he had two drinks. The speed limit on the Williamsburg Bridge is 35 miles per hour.

Police Office Matthew Mauro testified that Hoyte appeared to be intoxicated that morning, and that his breath smelled of alcohol.

Hoyte was arraigned late Thursday night and charged with vehicular manslaughter, assault, and operating a vehicle while intoxicated. He is currently being held on $100,000 bail.

Lawyer Scott Cerbin, who is representing Hoyte, told Gothamist on Friday that he believes "there is a substantial amount of evidence that this was an accident."

"We had a record blizzard and ice accumulation less than 24 hours earlier," Cerbin said. He also referenced a Daily News report that the barrier Hoyte struck had no reflector. (A neighbor told the tabloid that he had called 311 about the missing reflector on Wednesday, and stressed that "someone was going to get killed.")

"He said that the day before which is kind of interesting," Cerbin added. "The divider pops up in the middle which is hard to see."

Sources told DNAInfo this week that Hoyte had a blood alcohol level of .103 percent, well above the legal limit of .08 percent. Cerbin called this an allegation, and said he did not have any chemical test results.

Miner was on track to graduate from Lafayette College in Pennsylvania next year, according to a report in the school paper. She was studying anthropology and sociology, and was home in Brooklyn this week for spring break. Her advisor, Professor David Shulman, said in a message from the college president that Miner "just radiated niceness" and had a "great, winning personality."

She "spoke often, and had smart things to say. And she would speak her mind. If she had an opinion, she was going to offer it," he added.

Miner's mother told DNAInfo that her daughter was hoping to study social work after college. "She could have changed the world," Virginia Cabrera-Miner said.

Hoyte's next court date is set for March 21st in Manhattan.