A 21-year-old woman driving the wrong way through the Post Road/Kings Highway Cutoff traffic circle Sunday night, triggering a serious two-car crash that sent four people to the hospital, had marijuana and anti-psychotic pills in her car, police said.

The crash sent the young woman and the family in a pickup truck that she hit head-on, to hospitals in Bridgeport. Police said the woman, who had to extricated from her car, suffered “complex, compound fractures” to both her legs.

The three family members in the pickup, including an 8-year-old boy, were treated and released from Bridgeport Hospital.

The other driver’s condition at St. Vincent’s Medical Center in Bridgeport, was not known as of Monday night. She was not identified since charges had not been filed in the case.

The trapped driver — the lone occupant of a Honda— was extricated from the wreck by an operation carried out by 14 emergency responders using hydraulic rescue tools.

According to witness reports, the woman was driving the wrong way down the Post Road as she entered the traffic circle near McDonald’s restaurant about 6 p.m. Sunday, and was driving at “highway speed,” police said. She was unconscious when emergency personnel arrived at the scene, according to police.

Police said she had quit her job at a Westport hotel earlier that day, according to her father, and came home. She later went out with friends, but at this point in the investigation, police said Monday they do not know where she was immediately prior to the accident.

In her car, police said they found a glass jar and a pill bottle with marijuana and the prescription medication seroquel. In her purse was a burnt marijuana “blunt,” and a package of cigars typically used to make a blunt, according to the report.

Police Lt. James Perez said the department has the necessary software to obtain data on the speed of the woman’s car from the vehicle’s black box.

Fire crews at the scene included Engine 1, Ladder 1, Engine 2, Ladder 2 and Car 3, with assistance from the Southport Fire Department.