OAKLAND — A firefighter was injured early Thursday during a blaze at a vacant Victorian house in West Oakland, officials said.

The firefighter suffered a laceration to his hand from a glass shard and was treated and released at a hospital, officials said.

The fire started just after 1 a.m. Thursday on the top floor of a two-story Victorian house in the 1400 block of 12th Street.

The home was boarded up and possibly undergoing renovation, but there were signs it had been occupied by squatters, officials said.

The fire was brought under control within 25 minutes by 28 firefighters who prevented it from spreading to adjacent homes, Battalion Chief James Bowron said.

The exact cause of the fire is under investigation.

Bowron estimated damage to be in excess of at least $50,000.