Los Angeles, Mar 16 (IANS): At least three people were killed after a vehicle ploughed into a group of pedestrians in the US city of San Diego, police said.

The 71-year-old driver has been detained on suspicion of driving under the influence (DUI), reports Xinhua news agency.

The incident, which occurred on Monday just two blocks away from the San Diego Police Department (SDPD) headquarters, also injured six people, who are currently hospitalised.

"I don't know if people were sleeping, if people were sitting there," SDPD Chief David Nisleit told reporters during a press conference later in the day, only confirming at least nine pedestrians in the tunnel under the bridge were hit.

Nisleit also reported that the driver, whose name was not immediately released, had been detained on suspicion of DUI, and an hour before the incident, police received a call from a person reporting a possibly intoxicated driver in a Volvo running about a mile away from the bridge.

Meanwhile, the local CBS 8 news channel reported that the suspect tried to render aid to the victims who were hit prior to the arrival of emergency crews and he was arrested after being questioned by officers.