The Aichi Prefectural Police said Friday that the 19-year-old Nagoya University student who has admitted killing a 77-year-old woman last month apparently used her cellphone to take pictures of the victim's corpse.

The police confiscated the phone from the student's Nagoya apartment, where Tomoko Mori's body was found. They said they were still trying to verify when the photos were taken and why.

The student, whose name is being withheld as she is a minor, was arrested Tuesday. She killed Mori by hitting her with a hatchet on Dec. 7, police said.