4-year-old twins among 4 found dead at San Mateo home, sources tell ABC7 I-Team

SAN MATEO, Calif. -- Four people were found dead inside of a home in San Mateo's Sugarloaf neighborhood Monday morning after authorities were called to the scene for a welfare check, police said.

UPDATE: Family of 4 found dead in San Mateo murder-suicide identified, police say

San Mateo police say the home is located in the 4100 block of Alameda de las Pulgas near Fernwood St.

Police say a man, woman and two young children were found dead in the home.

The two young children are 4-year-old twin boys, sources told the ABC7 I-Team.

"Unfortunately, we located four deceased people inside the home. One adult male. One adult female and two children," said Jerami Surratt, public information officer with the San Mateo Police Department.

Residents say this is a quiet, suburban, safe neighborhood. They never thought something like this would happen.

"Streets closed between 41st and 42nd, and I am going, 'that is my area,'" said Donnita McDevitt, who was on a routine walk around the block when she saw the police tape.

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"It is quiet, safe, I walk it every other day at least, and this breaks my heart," she said.

Never did she think her almost daily walks would involve being near a crime scene.

"This is just not the norm for this area. I mean it has turned out to be a crazy world out there now, but this in our area of Westwood Knolls? No no."

Resident Bob Mateus grew up in the area.

"It's terribly tragic, we don't have anything like that. I grew up here," Mateus said.

Ronna McMurray said she walks by that house every night.

"We can only assume what has happened - whatever has happened is a major tragedy and you wonder what could've been done to avoid it," McMurray said.

Investigators had the road blocked off for most of the day.

Police could not say if a weapon was involved or recovered.

No further information about cause of death was available, but police investigating the scene say there is no sign of forced entry, and this is an isolated incident.

Investigators say they are not looking for any suspects.

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