The alleged domestic assault and battery that led to the arrest of Rep. Carlos Henriquez (D-Dorchester) on Sunday began in the backseat of a car on a quiet street in Arlington Heights, according to a new, more detailed police report.

Henriquez will face three counts of assault and battery, as well as charges of kidnapping, witness intimidation and larceny in Cambridge District Court. On Monday he pleaded not guilty to charges of domestic kidnapping, witness intimidation and larceny. Henriquez is scheduled to be arraigned at the court, which is in Medford, on July 31, the last day for formal legislative sessions and likely a busy one for the Massachusetts House.

According to an Arlington police report, Henriquez had been texting back and forth with 23-year-old Katherine Gonzalves on Saturday night, and around 3 a.m. Sunday, he showed up outside her mother’s house in a Zipcar. Gonzalves’ mother asked her not to leave so Gonzalves told her mother that she would be back when she went out to meet the first-term 35-year-old state lawmaker.

The couple parked a little ways down the street and moved to the backseat of the car – described as a blue Honda hatchback in the Boston Police report – where Gonzalves expected to kiss Henriquez for a while. Then she told him that she would not be able to leave with him that night, and he allegedly became angry, saying, “You made me come all this way,” according to the police report, which the News Service obtained Friday morning.

Henriquez allegedly back-handed Gonzalves across the face, grabbed her by the throat and then punched her in the chest, while Gonzalves cried, she told police. When Gonzalves attempted to document what was happening with her cell phone, Henriquez allegedly ripped it from her hands.

Then, as Gonzalves was still in the backseat, Henriquez drove off, getting onto Route 2 and heading into Boston. As Henriquez was stopped at a red light on Forsyth Street in Boston, Gonzalves leapt from the car, losing a flip flop in the process. She was then helped by someone who alerted a Northeastern University security guard, who in turn summoned the Boston Police, who arrived around 4:25 a.m.

Gonzalves had grabbed her phone back shortly before jumping out of the car, but she later discovered that it was missing its memory card.

Reached Friday afternoon, Henriquez attorney Stephanie Soriano-Mills said she had not seen the new police report.

“I’m interested to see what details she’s provided but he maintains his innocence,” Soriano-Mills said.

On Monday, after his arraignment in Roxbury Municipal Court, Henriquez released a statement proclaiming his innocence, saying he would be “vindicated” during the court process, and touting his work with groups that fight domestic violence.

“This matter will be tried in the court and not in the media or in the court of public opinion. I can assure my supporters and critics alike that I am innocent of these charges,” Henriquez said in the statement, calling the allegations “completely untrue.”

Two days later, Gonzalves, an East Somerville resident, held a press conference with her mother at her pro bono attorneys’ offices in the Back Bay, in which she said everything she told Boston Police was true. Henriquez did not tell his side of the story to Boston Police when he was arrested early Sunday, according to the Boston Police report. The alleged crime is suspected to have occurred in two jurisdictions, Middlesex County and Suffolk County.

Henriquez had spent the earlier part of that day and evening at a block party called ProjectV on Wendover Street in Uphams Corner not far from the lawmaker’s home, according to his Twitter feed. According to what Gonzalves told Arlington Police, Henriquez had the smell of alcohol on his breath when he arrived to pick her up. Gonzalves had spent the day at a “family get-together” at her mother’s house, according to the police report.

The Arlington Police report says Henriquez arrived at Gonzalves’ mother’s home around 3 a.m. to 3:30 a.m., which is about an hour later than Henriquez’s arrival in the original Boston Police report.

Gonzalves’ pro bono attorney Rick Brody told reporters that Gonzalves had heard Henriquez speak about the three-strikes criminal sentencing law at the Lowell Memorial Auditorium, agreed with his point of view and asked to interview him for a college essay.

According to the Arlington Police report, Gonzalves met Henriquez at a community meeting in Boston. The relationship was professional at first, and the two went on their first date in March 2012, according to the Arlington report. Arlington Police interviewed Gonzalves on Monday and the criminal complaint was issued on Wednesday.

Gonzalves told police it was the first time Henriquez had become violent toward her, but she said that during two arguments, Henriquez had grabbed her phone and looked through it.