Police in the central Italian town of Perugia have been carrying out a detailed search of a flat where a British student was found murdered.
Meredith Kercher was on a study year in Perugia
Meredith Kercher, 21, was found on Friday afternoon with her throat cut in an apartment she shared.
Bloodstains were found in the bathroom and her bedroom door was locked from the inside while her window was broken.
Her father John said he was due to fly to Italy, and the Foreign Office said it was working with Italian officials.
Miss Kercher, from Coulsdon, south London, had been on a study year from Leeds University.
Police are said to be examining her phone, found in a nearby garden before her body was discovered, and a second phone found near her body.
Police discovered her body in her locked bedroom
Police are also keen to trace an Italian boyfriend and a missing key used to lock Miss Kercher's door.
They also recovered a bloodstained handkerchief from close to the apartment.
Police said Miss Kercher had watched a film at a friend's house on Thursday evening but returned home alone to the apartment she shared with three others.
BBC correspondent Christian Fraser said the door to the bedroom in which she was found had been locked from the inside and it is thought the murderer may have left through a broken window.