SAN JOSE (KRON/BCN) — A three alarm fire destroyed a large barn and an outbuilding, and prompted a shelter in place advisory in San Jose early Tuesday morning, fire officials said.

Fire crews were called to the scene at 1186 E. William Court at 12:12 a.m. to find flames spreading through two structures, according to Capt. Mike Van Elgort.

Crews quickly called a third-alarm because of the size of the fire and the dry conditions, Van Elgort said. Flames also threatened about half a dozen homes.

It took firefighters about two hours to get the flames under control. No animals were inside the barn and no one was hurt, Van Elgort said.

Investigators believe the blaze was related to homeless people living in the barn. Officials say no one was inside the building when crews arrived. The exact cause of the fire is under investigation.

Neighbors were advised to shelter in place while firefighters worked to extinguish the blaze, fire officials said.