Authorities investigate Tuesday at a Herndon home where four family members were found dead. (Dayna Smith/The Washington Post)

A Fairfax County couple and their two school-age children were found dead in their Herndon home Tuesday by officers who were called to check on them, county police said.

Police did not immediately release the identities of the family members or provide a cause of death but said that they did not believe there was any ongoing threat to the public and that the incident was “contained within the household.” They declined to discuss whether the case was being investigated as a murder-suicide.

Officers discovered the bodies shortly after noon while performing the welfare check at the home in the 13300 block of Point Rider Lane near Frying Pan Farm Park, police said. A colleague of one of the parents had called police shortly after 10:30 a.m. Tuesday to report that the person had not been to work on Monday or Tuesday.

Police later determined that the children found dead at the home had not attended their Fairfax schools this week either, police said. Police declined to release additional details about the case.

On Tuesday evening, the bodies remained inside the single-family brick home, which was surrounded by yellow crime tape. Crime scene technicians and detectives went in and out of the front door as they collected evidence.

“The tedious process of technicians going through the scene and processing the evidence is what our delay is now in releasing more information,” Fairfax County police officer Eddy Azcarate said.

Neighbors said a couple had lived in the home for nearly three decades. They said the pair had a son in high school and one in middle school. Police declined to confirm the bodies were those of the family.

The neighbors described the family as a friendly fixture in the neighborhood.

Their corner home is at the junction of two streets, and neighbors said they would often sit on their front porch, wave to people passing by and grill on a barbecue. The sons, who played soccer, were regularly seen playing in the front yard.

Jim Steele, who lives nearby, described the father as “really a nice guy and civic-minded.” “He would hook up a blade to the front of his pickup and help people remove snow on the street,” Steele said.

Neighbors said they had not seen anything out of the ordinary at the home in recent weeks and months. Members of the family attended a back-to-school picnic on Sunday evening and a back-to-school function on the previous Wednesday, neighbors said. Relatives of the family did not return calls for comment Tuesday.

It was the largest number of people found dead in a single incident in Fairfax since a man went on a rampage on Christmas Day in 2005, taking the lives of his mother and three other people in McLean and Great Falls.

Several neighbors who gathered near the Herndon home Tuesday cried and hugged each other.

“The oddest observation for me is them not being on that front porch,” said one neighbor, who declined to be identified.