A teenage girl plunged 25ft to her death from a balcony early on Saturday.
The 17-year-old suffered massive head injuries after falling from the four-storey block of flats at 2am.
A passer-by raised the alarm after spotting the girl slumped in a pool of blood at the front of the building in Devonshire Road, Hastings.
The girl, who was local, was taken to the Conquest Hospital in Hastings but is understood to have been dead on arrival.
Police carried out house-to-house inquiries but last night said there were few clues as to why she had fallen.
Sergeant Gary Batcheler, of Hastings police, said the incident was being treated as suspicious.
The results of a post-mortem were today being passed to East Sussex coroner Alan Craze. An inquest will be held.
Sgt Batcheler said test results and identification would not be released until one of the girl's parents, who is abroad, had been informed.
Detective Inspector Nigel Smith, said: "The details are extremely sketchy."
Neighbours in Devonshire Road spoke of their shock. One said: "My friend knew her. She was really pretty with lovely blonde hair.
"I think it is terrible as she was so young and obviously had so much to live for."
Self-employed decorator Shon Williams, 32, said: "It's shocking to think something so tragic could happen so close.
"This is normally a quiet area and one of the last places you would expect something like this to happen.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article