A man attacked two elderly women with an ax in Hino, western Tokyo, on Friday night and fled the scene, police said.
A nearby resident was asked to make an emergency call and reported that the women were assaulted by their sibling at home at around 7:50 p.m.
The police are investigating the case as attempted murder. The suspect, also apparently elderly, left the ax behind.
The man was wearing a blue shirt and brown sandals, according to the police.