The woman pedestrian who was struck by a Honda Civic on Monday has been identified as Mariam Hedayati, officials said.
The 43-year-old Laguna Niguel resident was in crosswalk at Moulton and Aliso Niguel roads around 2:45 p.m. when she was hit.
"She did suffer head trauma and her left leg was amputated due to the collision," sheriff's spokeswoman Gail Krause said.
Heyadayti remained in critical condition Tuesday at Mission Hospital in Mission Viejo, according to the hospital.
An investigation of the accident is underway. The driver, a 45-year-old man whose name has not been revealed, was released Monday after being detained by deputies. He also suffered minor injuries, as did a motorcycle deputy in a separate accident at the scene.
After the pedestrian collision, a SigAlert closed down Moulton Parkway for five hours.