Masked men used a sledgehammer to shatter a sliding glass door and break into a West Covina home, where they tied up and gagged family members.
The men then ransacked the home and fled, police said. A detailed description of the four men sought by the West Covina Police Department was not available.
The crime occurred about 1:30 a.m. in the 3400 block of South Flemington Drive, police said.
No injuries were reported. No details were released about what was taken.
Anyone with information on the crime was urged to call police at 626-939-8500.