Arson investigators are trying to figure out what sparked a fire at a southwest Houston apartment complex Tuesday morning.

According to the Houston Fire Department, the fire started at the Summer Vale Apartments on Pagewood Lane around 12:30 a.m. The fire started in the attic of a vacant apartment under construction. Crews managed to contain the flames before they could spread to other rooms.

While some surrounding units suffered minor water damage, most residents were able to stay the night in their apartments. One resident went to stay with a friend.

The fire department said nobody was injured.