SAN DIEGO -- A $10,000 reward was offered Thursday for information leading to the arrest of a man who assaulted another man on the San Diego Trolley last month.

The attack occurred about 8:40 p.m. Nov. 27 after a black male stepped onto the trolley, made eye contact with a white man and then made "racially motivated, derogatory" remarks, according to San Diego police.

The man continued to make the remarks while pacing back and forth on the eastbound trolley and turning up the volume on a boom box he carried, authorities said.

At the Euclid Avenue stop, the assailant punched the man in the head, knocking him down. He continued to hit the man in the face and head until he ran from responding trolley officers, police said.

The officers pepper-sprayed the assailant during a struggle outside of the trolley, but he was able to escape.

The victim was taken to a hospital, where he got 13 stitches, police said.

The assailant is about 6 feet tall with an average build. He was last seen wearing red shorts and red and white Adidas shoes.

Anybody with information on the suspect was asked to call Crime Stoppers at 888-580-TIPS. Tipsters are eligible for up to a $10,000 reward, and may remain anonymous.