Police outside Philadelphia have arrested a woman on charges connected with the death of a 21-year-old pregnant woman who was found dead in a pile of debris earlier this week.

Tylydiah Garnett was seen on video helping dispose of Dianna Brice’s body, police sources told CBS3, and officers recovered clothing with burn marks.

Garnett has been charged with arson, abuse of a corpse, criminal conspiracy, and other related offenses, Fox 29 reported.

Brice was last seen with her boyfriend, 23-year-old Justin Smith, outside a Lansdowne laundry on March 30, as CrimeOnline previously reported. Her body was found in southwest Philadelphia nearly a week later, less than a mile from where Smith’s car was found ablaze on the day Brice disappeared.

Upper Darby police said an arson detection dog hit several times while sniffing the car. Police then turned their attention to another car — a white Hyundai reportedly rented by another of Smith’s girlfriends — and believed to have been used to transport Brice’s body, Fox 29 said.

Smith has not been seen or heard from since March 30 when Brice’s mother said he became angry when she called him asking about Brice’s whereabouts and said she was going to file a missing persons report. Shortly after that call, his car was found ablaze. His wallet and car keys were found nearby, and his phone has been switched off since that time.

Police said they used cell phone data to track Brice and Smith to west Philadelphia. Brice’s body was found in a wooded area on the 5800 block of Eastwick Avenue.

An autopsy report said Brice died from multiple gunshot wounds to the head.

Investigators have not revealed details of how they think Garnett was involved in the murder. Smith is still a person of interest in the case, they said.

Brice, the mother of a four-year-old son, was 4 1/2 months pregnant with her second child.

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[Featured image: Dianna Brice/Facebook]