Sheriff's deputies responded early Tuesday morning to the 4800 block of Alta Canyada Road in La Cañada Flintridge after receiving a call for help from three women who had locked themselves in a bathroom to avoid another woman who allegedly had forced her way into the home and was threatening them.
Investigators say the alleged intruder, 22-year-old Christina Sica of Arroyo Grande, was a former girlfriend of one of the victims.
"This is a relationship-related incident. This is not an unknown predator preying on the general public," said Sgt. Ray Harley.
Sica was found unarmed and hiding in a closet inside the home. She was arrested and booked at the Crescenta Valley Sheriff's Station on charges of burglary, which applies to attempts to enter a home with intent to commit a felony, and false imprisonment.
"It was pretty loud — woke us up in the middle of the night," said a neighbor who as early as 2:30 a.m. heard at least two women arguing.
A gate securing the home's driveway entrance was locked Wednesday and no one there could be reached.