Updated

A California home at the center of a police standoff Friday before being engulfed in flames, was later found to be empty, KGO-TV reported.

The fire started after SWAT police officers fired tear gas canisters into the house on Castlewood Drive in Vallejo, Calif., just north of San Francisco.

Police had surrounded the home as they closed in on six men being sought in connection with a Craigslist-related robbery, the Vallejo Times-Herald reported.

The robbery victim told police he had arranged to buy an item at an address in the 1400 block of North Camino Alto, but was set upon by the suspects when he arrived. The victim sustained head injuries and was hospitalized as of Friday night, police said.

Officers refused to reveal the nature of the item being sold in the transaction, but said a suspect vehicle was spotted at the Castlewood Drive property, which led to the standoff.

After unsuccessful attempts to contact people in the home, officers fired "non-flammable, non incendiary C.S. [tear] gas" into the property, police said.

Less than half an hour later police heard possible gunfire at the property and smoke was seen coming from the roof. After the blaze was extinguished, a search of the property found no one was inside, however two dead dogs were found.

The six robbery suspects are still on the loose.