ABC News May 17, 2015

Police Release Surveillance Footage of Person of Interest in Deadly Washington, DC, Mansion Fire

WATCH: Surveillance Footage May Provide Lead in DC Mansion Fire Case

Police released surveillance video of a person of interest in the deadly blaze that killed a family of four in a Washington D.C. home last week.

The video, released Saturday night, shows a hooded figure carrying a white object, running past an unidentified building.

VIDEO: Person of Interest Caught on Surveillance Video

The video also shows a "vehicle of interest," a blue Porsche convertible with D.C. license plates registered to the family, which was seen at the house before the fire broke out.

Couple Identified in Mystery Mansion Fire: What We Know About the Deadly Washington, DC, Blaze Annapolis, Maryland, Mansion Fire: Searchers Find Fifth Body Annapolis, Maryland, Mansion Fire: What the Family Did Hours Before Deadly Blaze

Police said the car was later abandoned and set on fire on Arlington Road in Prince George’s County.

Two of the identities of the victims -- Savvas P. Savopoulos, a 46-year-old corporate executive, and his wife, Amy -- were confirmed by police in a press conference on Friday.

The two other bodies are not identified but are believed to be the couple's 10 year old son and the family's housekeeper, police said.

The fire is being investigated as a homicide and arson. Blunt-force or sharp object injuries were found on at least three of the four victims, police said.

The fire was reported Thursday afternoon in an upscale neighborhood less than a mile from Vice President Joe Biden's home. According to real estate website Trulia, the home was assessed last year at more than $4 million.

"I've been here for 25 years and nothing like this ever happens. So it's really kind of just rattling," a neighbor said.