Search warrants filed Wednesday in the investigation of last month's murders of a wealthy Washington D.C. family and their housekeeper say cell phones belonging to the victims were stolen from the mansion where the crimes took place and authorities believe there was forced entry into the home on the day of the killings.

Savvas Savopoulos, his wife Amy, their 10-year-old son Philip and Veralicia Figueroa were found dead by firefighters on May 14 while battling a fire at their home in the upscale Woodley Park neighborhood of Washington D.C., not far from the Vice President's official residence. Their deaths were ruled to be homicides.

According to three search warrant affidavits, cell phones belonging to Savvas and Amy Savopoulos, as well as Figueroa, were stolen from the home after the May 14 murders. Investigators hoped data from those phones would lead them to the suspects in the case.

A fourth unsealed warrant is for the phone records of Savopoulos' assistant, Jordan Wallace, who delivered $40,000 in a package to the family's home on the day the victims were found dead on the second floor of the house.

A fifth search warrant is for two vehicles that were stopped by authorities during the May 21 arrest of Darron Wint in connection with the murders. Wint, who is charged with first-degree murder while armed, is the only person who has been charged in the case, though investigators believe, in the words of the affidavit, that "the crimes described in this affidavit required the presence and assistance of more than one person."

Wint was named as a suspect after police found DNA linking him to a partially eaten pizza crust that was delivered to the Savopoulos' house on May 13, the night before the bodies were found.

The fifth search warrant says a shoe or boot print was found by investigators on one of the Savopoulos home's French-style doors, suggesting there was forced entry into the house. The door had a single broken window pane and had suffered damage near the lock. Investigators are now searching for any shoe or boot with a similar tread pattern.

This search warrant also says investigators searched a car that Wint was riding in for a digital video recorder that may have been used to capture and store surveillance video at the Savopoulos' house.

On Tuesday, D.C. police investigators were back at the Savopoulos' home examining a large safe in the garage. Investigators were also seen combing through documents and other items in a second-floor bedroom.

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