Santa Rosa police were investigating a head-on collision Tuesday night that injured four motorists on Sonoma Avenue, just west of Summerfield Road.

The 6:48 p.m. crash involved three motorists in a Cruiser PT Cruiser and one in a Volkswagen Passat. All were trapped and had to be extricated by Santa Rosa firefighters. Their injuries ranged from minor to moderate and they were taken to Santa Rosa Memorial Hospital.

Police blocked east and westbound traffic on Sonoma Avenue for about an hour and a half while the accident was investigated and vehicles removed. People were asked to avoid the area through a Nixle alert.

Area residents came out to see the two cars in the middle of the street. The cars’ front ends were badly smashed.

One young girl whose apartment is close to Sonoma Avenue said the crash sounded like a thunder clap.

Anyone with information regarding the collision was asked to contact Officer Woods of the Santa Rosa Police Department Traffic Division at 707-543-3636

You can reach Staff Writer Martin Espinoza at 707-521-5213 or martin.espinoza@pressdemocrat.com. On Twitter @renofish.