2011-08-05 06:02:00 A.M. -- A 9-year-old boy was hit in a downtown San Francisco intersection by a truck that police believe drove away onto a nearby freeway Thursday night.

The boy was hospitalized and is being treated for life-threatening injuries after a white Toyota pickup truck struck him as he was crossing Mission Street at New Montgomery Street around 10:30 p.m., police said.

The boy was walking ahead of a family member when the truck turned left onto Mission Street after driving north on New Montgomery Street, which is a one-way street with traffic only in the southbound direction, police said.

The truck did not stop and continued driving west on Mission Street after hitting the boy before colliding with numerous other cars parked and driving on the street. The suspect continued driving in the pickup truck and reportedly entered a nearby freeway, police said.

Police sent a "be on the look out" message to Bay Area law enforcement agencies to alert them of the suspect vehicle, which possibly has front-end damage.

The area around Mission and New Montgomery streets is considered a crime scene and will be closed to vehicles and pedestrians for several hours as police investigate the accident, police said.

Police personnel are working to provide emotional support and counseling services to the family of the victim.

Witnesses are encouraged to call the Police Department at (415) 553-0123 or the anonymous tip line at (415) 575-4444 or send a tip by text message to TIP411 with "SFPD" in the beginning of the text message.