SAN ANTONIO -

Fire officials are looking into what caused a west side house to break out in flames Thursday afternoon.

The fire broke out just before 5 p.m. at a house in the 2100 block of Cross Key.

When crews got to the scene, no one was inside the house. So they had to break a door to get in.

Fire officials said it appears the fire started in the den, towards the left side of the house and then spread up a wall to the attic.

While crews did contain the fire, there was still a lot of smoke and water damage to the rest of the house.

"I guess with the wind and the dryness we had, it just really, the fire really took off," said Sylvia Belous, a neighbor.

Fire officials said there were about five or six dead cats found under a couch.

The cause of the fire is still under investigation.