A four-car accident occurred Tuesday around 8 p.m. on Lake Merced Boulevard near Mary Park Hall, sending one woman to the hospital.

According to witnesses, a Western Eagle Shuttle driving passengers home from San Francisco International Airport collided with the rear of a Subaru Forester, shattering the back window and sending glass onto the hood and roof of the van. None of the shuttle’s passengers were hurt.

Witnesses said paramedics took the unidentified driver of the Subaru to the hospital.

The impact from the shuttle and the Subaru's collision caused a chain reaction, leading to the pileup that involved nine people, including two passengers who complained about pain after the accident.

The driver of one of the cars was Richard Fierro, who was heading home at the time of the accident and said his back was bruised.

He received no examination from paramedics who were anxious to get the woman to the hospital, he said.

Police have not yet released an official statement about the cause of the accident or the injuries.

The van’s driver, Georgi Nikkolov, sustained no injuries. He said the unidentified driver of the Subaru had cut her car in front of the van. Nikkolov said he was not driving fast and the accident was not his fault.

He had taken Lake Merced Boulevard instead of 19th Avenue to avoid traffic.

Stephen Martinez, the driver of the car that was hit last, said the driver of the airport shuttle caused the accident.

“I’m pretty sure it was the van,” said Martinez, a Vallejo resident. Martinez said he experienced a headache after the accident.

“Jolly way to end an evening,” said Hope Herndon, a shuttle passenger who was returning home after flying across the Pacific Ocean from Fiji.