The Metropolitan Police Department has arrested the husband of Ai Kago, an ex-member of all-girl J-pop idol group Morning Musume, for allegedly assaulting her, investigative sources said Tuesday.

Haruhiko Kago, 47, was arrested after allegedly attacking the 27-year-old singer, including by kicking her, in a Roppongi-district condominium in Tokyo's Minato Ward on May 12. The assault left her with bruises on her neck and the limbs on her right side, the sources said. Her husband, a company official, has denied the allegation.

Police said they expected it would take 10 days for her injuries to heal.

They started to investigate the allegation after she reported the assault, the sources said.