New video shows slain jogger Karina Vetrano on her last run, moments before she was found dead in New York.
The surveillance footage, obtained by US TV program Crime Watch Daily, shows the 30-year-old running near Spring Creek Park in Howard Beach on August 2.
The video was taken at 5.46pm, minutes before authorities believe she was sexually assaulted and five hours before her body was found.
NYPD Chief of Detectives Robert Boyce said authorities had three pieces of DNA to develop a profile of the killer. So far, they haven't found any matches.
"She was beaten around the face. She was punched in the teeth," Boyce said. "She also had bruising on her body, we believe from being dragged through those weeds."
He said Vetrano's ex-boyfriend and family members have been ruled out as suspects.
Vetrano's body was found at 10.30pm by her father, Philip. He said he normally went for jogs with his daughter, but didn't that night due to an injury.
The grief-stricken father has started a GoFundMe page to raise money to supplement the $US20,000 reward offered by the NYPD in their hunt for the killer.
Earlier this month, police released a sketch of a potential witness they want to question over Vetrano's murder.
Boyce said the man in the sketch has no direct connection to the killing but was seen by a utility worker the bike path in Spring Creek Park at the time of the attack.
Detectives think the man, who is believed to be between 35 and 40, might be able to provide information about Vetrano's sexual assault and murder.