SAN JOSE -- Fire officials are investigating what caused a small blaze to break out overnight at a private school in San Jose, according to a San Jose Fire Department captain.

San Jose firefighters responded to St. Thomas More School, located at 1565 South White Road, after receiving reports from an alarm company that sprinklers had been activated, according to San Jose fire Capt. Mary Gutierrez.

San Jose firefighters initially said the small blaze may have been suspicious. Fire investigators initially thought a candle may have started the blaze, but are now looking at other causes, Gutierrez said.

Firefighters responded to the school to investigate and located water flow and smoke inside an office area, Gutierrez said. There had been a small fire contained to a school office, Gutierrez said.

A fire cause investigator was sent to the school, Gutierrez said.

Firefighters called for a full first alarm at 1:10 a.m. and had everything under control by 1:36 a.m., Gutierrez said.

Contact Mark Gomez at 408-920-5869. Follow him on Twitter @MarkMgomez