A woman found dead in the grounds of an east London Baptist church suffered fatal head injuries, police said.
The victim, who has been named as 41-year-old Kelly Stewart, was declared dead at the scene in Barking Road, Plaistow, on Thursday.
Officers were called to the Memorial Community Church at around 3.10pm. Police believe she was attacked between 12.45am and 1.45am that day.
Detectives are keen to speak to anyone who was in contact with Ms Stewart in the weeks before her death.
Detective Inspector Darren Jones of the Metropolitan Police, who is leading the investigation, said: "We are working hard to establish exactly what happened to Kelly, and we must keep an open mind as to any motive.
"There is a dedicated team of officers who are exploring every single avenue to track down the person or persons responsible.
"I need to hear from any witnesses and anyone who may have information that will assist the investigation.
"I also want to hear from anyone who knew Kelly, who was in contact with her in the weeks before her death and who may know the people with whom she was associating."
Ms Stewart was of no fixed abode at the time of her death, but was from the Newham area.
A post-mortem examination gave the cause of death as impact injuries to the head.
Anyone with information is asked to call the incident room on 020 8345 1570 or call charity Crimestoppers anonymously on 0800 555111.