The carjacker forced his way into her Lexus, sideswiped a police cruiser and led officers on a chase that reached more than 100 mph Wednesday night, police said. The woman, who was in the car with her 20-month-old son, had a harrowing, split-second decision to make.

As the car rounded the outer loop of the Capital Beltway in Bethesda, police said, she clutched the toddler to her chest and dived out of the car.

“The front door opened, and she rolled out,” said Elena Russo, a Maryland State Police spokeswoman. “The second door hit her, and she continued to roll.”

The woman ended up in the third lane of the outer loop, just past the exit for Cabin John Parkway. The child, still in her arms, was unharmed, police said. The woman’s only physical injury was a gash on her head.

“I’m not a hero. I’m just a mom. That’s all,” the mother told WJLA-TV (Channel 7) outside her Baltimore home. The station identified her only as Elsya, 24.

Terron Alvin White, 22, of Baltimore was arrested soon after and charged with two counts of kidnapping, first- and second-degree assault, and vehicle theft, according to court documents.

The dramatic ending capped a wild, 45-minute ordeal that began at a Citgo station in Baltimore shortly after 10 p.m. Wednesday, police said. White allegedly forced his way into the four-door Lexus GS 300 and drove off with the woman and child inside. On his way out of the filling station on Edmonson Avenue, White allegedly hit another car, police said.

About 10:30 p.m., the Lexus sideswiped a state police cruiser that was parked on the shoulder of southbound Interstate 95 near the Riggs Road exit in Prince George’s County, police said. The cruiser was in a construction zone and had its emergency lights on.

The trooper flipped on his siren and immediately began chasing the car, according to police. The Lexus, headlights off, raced down I-95 at more than 100 mph and merged onto the Beltway headed toward Rockville, police said. The trooper radioed a description of the car to the Rockville barracks but lost track of the vehicle.

Another trooper spotted it at about 10:45 p.m. near the Connecticut Avenue exit and tried to pull it over, police said. White was driving about 45 mph at the time, according to police, and the passenger door of the Lexus appeared to be hanging open after the earlier crash with the police cruiser. The rear passenger door was also damaged.

White continued to drive erratically, changing lanes and speeding up to 60 mph and then slowing to 10 mph, police said. Russo said there might have been a physical struggle going on inside the car.

Eventually, four cruisers caught up with the Lexus and began trailing it, Russo said. A video camera mounted on the dashboard of one of the police vehicles captured a portion of the chase. Police declined to release the footage.

“The car was weaving in and out of traffic,” said Russo, who watched the video. “If you didn’t know better, you might think the driver was drunk. The victim’s hands were flailing outside the passenger-side window.”

As the vehicle slowed to 10 or 20 mph near the Cabin John Parkway exit, the woman jumped from the front passenger seat while holding the child, Russo said. She rolled about 10 feet.

The woman told Channel 7 that her biggest fear was dropping her son as she jumped. She said she held the boy tight against her chest.

Russo said the police cruisers were close enough to the Lexus to prevent any oncoming traffic from hitting the woman.

White then pulled over and was arrested, police said. The victims were taken to a hospital, where they were treated and released.

White passed a field sobriety test, and it did not appear that he knew the woman, who was not fully identified, Russo said.

White was scheduled to have an initial hearing in Montgomery County District Court on Thursday afternoon, Russo said. A bond hearing was tentatively scheduled for Friday. A Baltimore police spokesman said White will face charges there as well.

Russo said the woman was “very lucky” that she escaped more serious injury.