The reward money for information about whoever strangled a Northeast Philadelphia mother as she jogged through a city park earlier this week increased again as police investigators returned to the scene of the crime and revealed that the victim spoke to someone in a car in the moments before she was killed.

Philadelphia Police investigators returned to Pennypack Park Friday morning as they searched for clues in the strangulation death of 46-year-old Constance "Connie" Murray. Crews already cleared some of the brush around the area where Murray's body was found.

The Holme Circle mother was last seen alive when she went left her Tolbut Street home to go for a jog Monday night. Her family searched for her and then contacted police when they were unable to locate her.

A woman walking her dog found Murray's body Tuesday morning in the park near the Crispin Rec Center.

According to police, surveillance video shows Murray traveling down Willets Road to Convent Avenue and on to Holme Avenue Monday night. Police say Murray was carrying headphones and a cellphone with her shortly before her death. Those items have not been recovered.

The Medical examiner ruled Murray's death a homicide by strangulation.

"He did not see much sign of a struggle," said Philadelphia Police Homicide Division Cpt. James Clark. "There was some minor bruising on her."

Clark also said there were no signs of a sexual assault.

Detectives interviewed "a lot of people" in the neighborhood but no one, at this point, is a suspect. Clark said they also would like to speak to the driver seen on surveillance video stopping and talking to Murray "for a couple of seconds" in the moments before her death.

The City of Philadelphia, Citizens Crime Commission, Fraternal Order of Police, Philadelphia Parking Authority, District Council 21 Painters and Allied Trades and Philadelphia Federal Credit Union combined to offer a $51,000 reward for information leading to an arrest and conviction -- $30,000 of the reward money is offered for just an arrest in the case. The Parking Authority got involved since Murray's brother Kevin McClane works for the parking authority.

Colleen Gass, a family friend, told NBC10 she recently spoke with Murray's sister, who wanted to relay a safety message.

"Her sister wanted me to tell everyone not to wear earbuds while running," Gass said. "The whole reason she thinks her sister was attacked was because she didn't hear him coming. She had her earbuds in."

Captain Clark shared his own warning to those who frequent the park.

"Females out there walking or jogging should always be in the company of someone else," Clark said.

Police have no motive in the murder and say at this point it's unclear whether it was a random or targeted attack.

If you have any information on Murray's death, please call Philadelphia Police at 215-686-8477 or 215-546-TIPS to ensure you are considered for the reward.