A woman found dead in a park may have been murdered on Christmas Eve, police said.
Her body was found in a building by the sports ground in the middle of Finsbury Park, north London, on Wednesday, Scotland Yard said.
However, murder detectives believe she may have been killed several days previously.
Detective Chief Inspector Nicola Wall said: "We believe that this woman was attacked whilst in the park and this may have occurred on Christmas Eve.
"Her body was discovered in an outbuilding next to a sports pitch.
"We are trying to establish the motive for the attack and would like to hear from anyone who has seen anything suspicious in that part of Finsbury Park around the Christmas holiday period."
The body of the woman, thought to be aged in her 20s, was found shortly before 4.30pm by a member of the public.
She has yet to be formally identified and a post-mortem was due to take place on Thursday.