A Leeds student found murdered in Italy met her death at around 2am on Friday, it was revealed today.
The time of death discovered in a post-mortem examination yesterday was reported in the Italian press.
Meredith Kercher, 21, was found later that day with her throat cut in her bedroom in the central Italian city of Perugia.
Police in Perugia, where Meredith was found with her throat cut, are scouring photos taken at a Hallowe'en party last Wednesday.
Up to 250 snaps were posted on the social networking website Facebook, many on the 21-year-old's own page. Police are using the pictures to draw up a list of possible suspects.
Pasquale Pisco, co-owner of Merlin's Bar where the fancy dress party was held, said detectives had shown him several photos from the site.
He said: "If the killer was at the party then he could very well be in the photos (Meredith] posted on Facebook.
"It's a scary thought, but what if someone she met at the party followed her the next night?"
Yesterday a seven-hour post mortem examination confirmed Meredith had had sex shortly before she died but rape was ruled out.
She spent Thursday evening with some English friends but walked home alone around 9pm. It is thought she died at around 10pm.
Police are working on the theory that she knew her killer and let him into the house.
Her body was discovered in the bedroom on Friday afternoon. Police forced open the locked door to discover Meredith's body partially naked and hidden by a duvet. Her throat had cut wounds – possibly inflicted by a small pocket knife.
Blood was on the wall of her bedroom and in the bathroom. Neither the murder weapon or the key to the room have been found.
Police chief Marco Chiacchiera said they felt sure that Meredith knew her killer.
But he added: "As yet we have no definite suspect. One thing we can be fairly certain of is that Meredith knew her killer as the door of the house was not forced open."
Meredith's father John Kercher was today on his way to Italy to help police with inquiries. He is believed separated from his daughter's mother, Airlene, who lives in Coulsden, Surrey.
In an internet tribute, Meredith's aunt Sandra Jennings wrote: "Mez was a young, thoughtful person, kind to everyone. She will be missed by me and my family and all her relatives.
"Whoever did this has wrecked several lives."
Meredith was on her third year of a four-year European studies degree at Leeds University.
She was on an exchange year as part of her course in the quiet town of Perugia, around 100 miles from Rome.
The University has sent a representative to the town to help its other students still out there.
Her death comes less than eight months after former Leeds University student Lindsay Hawker,22, was murdered in Japan.
In March, the 22-year-old English language teacher, was found bound with gardening tape in a sand-filled bath on the balcony of a flat in Ichikawa, east of Tokyo.
Tatsuya Ichihashi, the only suspect in the case, has been on the run since police arrived at the flat.