CONCORD — A man suffered a "significant" head injury Thursday night when he was robbed while walking near downtown Concord, police said.

The victim, a 49-year-old man, was found lying on the ground in the 2200 block of Galindo Street about 10:30 p.m. by officers responding to reports that a man was down, police said. The man was taken to the hospital where he underwent surgery for a head injury. He is listed in critical but stable condition.

Few details are available, but police said the man was walking through the neighborhood when he was attacked and robbed. A passerby found the injured man and called police.

Anyone with information about the attack and robbery can contact police at 925-671-3220, the tip line at 925-603-5836, or Bay Area Crimestoppers at 1-800-222-8477 (TIPS).

Robert Salonga covers public safety. Reach him at 925-943-8013. Follow him at Twitter.com/robertsalonga.