An arson investigation was underway Wednesday after two new homes under construction went up in flames, fire officials said.
The blaze was reported about 1:10 a.m. in the 500 block of E. Desert Willow Road in Azusa, according to the Azusa Police Department.
The two-story single-family homes were fully engulfed in flames when fire crews arrived, Azusa Police Lt. Paul Dennis said.
Police received a report about the sound of two people arguing in the Rosedale community immediately before the fire, but police did not say it was related to the blaze.
Officials have not said what caused the fire, which caused $500,000 in damage.
It took nearly 30 firefighters about 40 minutes to knock down the flames, fire officials said. No injuries were reported in the blaze.
Police are asking anyone who has information about the fire or any suspicious people in the area to contact the Azusa Police Department.