PHILADELPHIA (CBS/AP) — A reward of $35,000 is now being offered for the arrest and conviction of the suspect responsible for the gruesome murder of a doctor who was found bound and burned inside her Center City apartment earlier this week.

Melissa Ketunuti’s partially nude body was found on fire by her dog walker in the basement of her row home in the 1700 block of Naudain Street Monday afternoon. (See Related Story).

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Investigators said the cause of death was likely strangulation: a rope had been found around her neck. Investigators also said Ketunuti’s wrists and ankles were tied behind her back.

During a news conference Tuesday, homicide division Captain James Clark said he did not believe she had been sexually assaulted.

Authorities said there were no signs of forced entry into the home.

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Clark said investigators were continuing to talk with neighbors and were analyzing surveillance tapes from the neighborhood. He said the doctor had a boyfriend, but he is not a suspect at this time.

Ketunuti worked as a pediatrician at Children’s Hospital of Philadelphia. The hospital issued a statement Tuesday, saying in part: “The entire community of the Children’s Hospital of Philadelphia is deeply saddened to learn of the tragic death of Dr. Melissa Ketunuti, a second-year infectious-diseases fellow and researcher at CHOP. Our thoughts and prayers are with her family, colleagues, and friends at this difficult time.”

Private donors have offered a $15,000 reward, which is in addition to a $20,000 reward that is already being offered by the city of Philadelphia.

Police are asking anyone who may have seen anything unusual in the neighborhood around 12:30 Monday to call 215.546.TIPS.

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