Bellevue police will provide 24-hour patrols in the neighborhood where a slide pushed a house off its foundation earlier this week following a break-in Thursday morning at a home that had been evacuated, police said.

“Security in this zone is a top concern for us,” interim police Chief Wendell Shirley said in a news release. “While our officers have been patrolling the slide zone on every shift, we are pleased the city has authorized us to provide off-duty officers as another line of security.”

The Monday landslide pushed a home in the city’s Somerset neighborhood off its foundation, forcing the evacuation of several homes. About 40 people were ordered to evacuate and take shelter in friends’ or relatives’ homes, or at the South Bellevue Community Center.

Around 8:30 a.m. Thursday, a homeowner confronted a man who had broken in the back door of one of the red-tagged homes, police said. The man then fled.

“This is a terrible incident and just adds to the stress of the situation for the affected homeowners,” City Manager Brad Miyake said in the news release.

Since the slide, the area near Southeast 51st Place and 139th Place Southeast has been closed off, and the immediate vicinity of the collapsed home remains restricted. Officials are asking the public to avoid the area.

An aerial look shows the hillside where a Bellevue home slid off its foundation early Monday. Forest Ridge School’s parking lot is above the home. (Steve Ringman / The Seattle Times)

State and city agencies and engineers continue to assess the safety and stability of the neighborhood.

Bellevue utilities confirmed an 8-inch water main break caused water to rush down the wooded hillside, but officials are still investigating what caused the landslide and the main to break, city officials said.

Seven homes remained red-tagged Thursday — unsafe to occupy. There’s no estimate for when displaced families will be able to safely return to their homes, city officials said.

The investigation into the cause of the slide could take weeks, “if not months,” to complete, the city said Wednesday.

Information from Seattle Times archives is included in this story.