A 6-year-old boy died Friday after his head was crushed in the revolving doors at the main entrance to the Mori Tower building in the Roppongi Hills complex in Minato Ward, Tokyo.

It was subsequently learned that the same doors injured two others late last year.

Ryo Mizokawa, of Suita, Osaka Prefecture, ran ahead of his mother while they were on a tour of the complex and got his head jammed in the revolving door at the main entrance on the second floor of the Mori Tower building at around 11:30 a.m., according to a police investigation.