Paul Saab and Christal Condon Saab live in the $15million home with their three young kids. Paul is a software engineer at Facebook and Christal is an angel investor. Records show that they bought the property in 2020. 

While digging up the yard to perform renovations, the couple's team of contractors discovered a car buried deep in the ground behind the house.  Cadaver dogs were brought in and detected a 'slight' possibility of human remains.

The car was registered to a previous owner of the home and police believe it is from the 1990s. That owner has not yet been named, but police are working to track them down for an interview. 

DailyMail.com has viewed property records which indicate the Lew family lived in the home between 1990 and 2014.

The unused bags of concrete were placed throughout the vehicle, though it was blanketed by dirt over the roof, he said.

The 1.63-acre property includes the 12,000sq ft home and was bought in 2020 by its current owners for $15million.

The mansion was built in 1990 and was sold in 2014 for $7.3million.

It has five bedrooms and seven bathrooms and features a private pool, and was listed for rent before the 2014 sale.

Atherton resident Athena Ogawa told NBC Bay Area: 'It's a mystery in my own neighborhood.'

Multiple squad cars, SUVs and firefighters came to help on the potential crime scene.

Meanwhile, Sky News reports that a convertible sports car stolen 30 years ago has been found buried in the yard of a California mansion built by a man with a history of arrests for murder, attempted murder and insurance fraud.

The car was reported stolen in September 1992 in nearby Palo Alto, Atherton town mayor Rick DeGolia said.

The sprawling home with a pool and tennis court was built by Johnny Lew, who spent time behind bars in the 1960s and 1970s.

He was found guilty of murdering a 21-year-old in Los Angeles in 1966, but the conviction was overturned two years later.

And in 1977, he spent three years in prison after being convicted of two counts of attempted murder.

In the late 1990s, he reportedly hired undercover police officers to take a $1.2m yacht "out west of the Golden Gate Bridge into international waters and put it on the bottom".

His daughter Jacq Searle told the San Francisco Chronicle that the family lived at the property in the 1990s - which is when Atherton Police believe the car was buried - and that her father had died in 2015 in Washington state.

Police commander Daniel Larsen would not say if police believe the vehicle was registered to Lew.

Although cadaver dogs alerted to possible human remains on Thursday, none had been found more than 24 hours after technicians began excavating the car.