PHILADELPHIA (CNN) -- Authorities have charged a Levittown, Pennsylvania, man in the death of a doctor whose bound body had been set on fire in her home, the Philadelphia district attorney's office said Thursday.
Jason Smith has been charged with murder, abuse of a corpse and other charges, according to Tasha Jamerson, a spokeswoman for the Philadelphia district attorney's office.
A law enforcement source said surveillance cameras captured the man entering 35-year-old Melissa Ketunuti's home in the Center City neighborhood of Philadelphia on Monday, the same day authorities say she was bound, strangled and her body set on fire in the basement of her row home on a quiet tree-lined Philadelphia street.
Ketunuti's dog walker discovered her body, according to police.
Investigators found no signs of a struggle, and no obvious signs of sexual assault, police said Tuesday at a news conference.
Investigators searched the man's home in Levittown on Wednesday and towed away his pickup truck, according to the source. Levittown is about 30 miles away from Ketunuti's home.
Police, who had posted a $20,000 reward for a conviction in her death, declined to say what led them to the man, who was in police custody Thursday. The man has no direct connection to the woman, according to the source.
While the surveillance video linked the man to Ketunuti's home, "there is much more to it than that," the source said.
Ketunuti, who graduated from medical school in 2007, moved to Philadelphia from Washington in 2008 for a three-year residency in pediatrics. She was in her second year of working as a researcher and fellow in infectious diseases, the hospital said.
She previously had residencies in surgery at Georgetown University Hospital in Washington and cardiothoracic surgery at a veterans hospital.
Susan Candiotti reported from New York, and Sarah Hoye reported from Philadelphia.
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