Three two-alarm fires that burned within a half-mile of each other and less than 12 hours apart are believed to be cases of arson, Vallejo Fire Department Chief Paige Meyers said Thursday afternoon.

"The way they were set and the form of the accelerant are similar. There were obvious signs of deliberately set fires," Meyers said.

The first fire, reported around 8:15 p.m. Wednesday, burned in a house in the 1400 block of Alabama Street.

The second blaze, at the Vintage Cocktail Lounge at 732 Tuolumne St., started around 2:30 a.m. today, and the third was reported at 7:30 a.m. today in a pet clinic at 1207 York St., Meyers said.

All the structures that burned were badly damaged, Meyers said.

All 18 firefighters and a battalion chief who were on duty responded to the blazes, Meyer said.

There were no witnesses, and Vallejo police are looking for suspects, Meyers said.