One person was crushed to death and five are injured after a small plane crashed into a car on a San Diego freeway, officials confirmed to NBC 7 San Diego.

The single-engine, two-seat Lancair IV crashed into a car on Interstate 15 North near State Route 76 at approximately 9:15 a.m. Saturday morning, about 50 miles north of San Diego.

“One witness stated that they didn't hear the engine of the plane. Witnesses are saying without question the plane appeared to be having mechanical issues,” Chris Parent of CHP said.

The driver, identified as Aaron Meccann, had pulled over to sync his Bluetooth when the plane crash landed in the fourth lane of the freeway, sliding 250 feet and hitting the back of the Nissan, CHP authorities on scene said. CHP officials said there was no evidence landing gear was deployed and it appeared the plane had mechanical issues.

See photos from the scene of the crash here.

Watch video from moments after the plane crash here (Warning: graphic language).

Authorities on scene told NBC 7 San Diego that a 38-year-old woman, identified as Antoinette Frances Isbelle, was sitting in the back passenger seat and was crushed to death at impact. Meccann, 43, who had pulled over to sync his Bluetooth, was taken to Palomar Hospital with lacerations above his eye; a 45-year-old female sitting in the front left passenger seat was taken to Sharp Linda Vista; a 36-year-old man sitting in the back passenger seat was taken to Sharp Linda Vista Hospital.

The pilot, a 60-year-old man, suffered severe head trauma, CHP officials said; his injuries are considered life-threatening. He was taken to Palomar Hospital. The passenger in the plane, a woman in her 50s, suffered non life-threatening injuries and was taken to Palomar Hospital.

Chris Saunders, a Palomar Hospital spokesman, said the extent of the victims' injuries and their conditions are unknown as they are in the ER.

Crews worked to clean up a fuel leak from either the plane or car following the crash.

Jacob Duncan was heading to work when he noticed a plane that appeared to be having trouble leveling out approaching the freeway.

“The plane touched down about 40 feet behind my car and it slid about another 40 feet,” Duncan recalled in an interview with NBC 7.

“One car was stopped on the shoulder,” he said. “It slammed right into the back of them.”

Duncan hopped out of his vehicle and with the help of other passersby tried to help the people in the aircraft and the vehicle.

Erika Uribe-Muñoz witnessed the crash and commented on NBC 7's Facebook page.

"We were on the opposite side of the freeway, we saw it as it was coming down to crash, pretty scary," she said.

Cyndi Young also saw the crash. "Was scary," she posted on our FB page. "Went right over our heads. Saw it hit the ground."

A Sig Alert was issued for the area as crews respond to the scene. Traffic quickly backed up in the area.

Duncan said in hindsight, it was obvious the pilot didn’t have much control of the plane and was trying his best to avoid the vehicles on the road.

“It’s sad for everyone involved,” he said.

If the car hadn’t been stopped on the freeway, Duncan said, he thinks the crash would’ve been avoidable.

“The pilot really I believe was trying his best,” he said.

Isbelle was a member of the San Diego Roller Derby according to the 'Aftershocks.' The team posted condolences on their Facebook page Saturday saying:

"We are hit very hard with the passing of Toni "Rockalicious" Isbelle. She was a great part of our family. Condolences to our sister league San Diego Roller Derby. Your big brothers will always be here for you for anything that you need. We love you Rockalicious!"

No other information was immediately available.

Check back for details on this developing story.