The family of a 6-year-old boy who was crushed in an automatic revolving door at Tokyo's Roppongi Hills commercial complex has reached an out-of-court settlement with the complex operator, sources said Monday.

In the settlement struck between the family of Ryo Mizokawa and Mori Building Co., the operator promised to pay an undisclosed amount in compensation and promised to take steps to prevent similar incidents in the future.

According to police investigations, Mizokawa died after getting his head stuck between the revolving door and door frame as he rushed through ahead of his mother at the second-floor front entrance of the Mori Tower building. The incident took place at around 11:30 a.m. March 26.

They were visiting Tokyo from Suita, Osaka Prefecture, where they lived.

Since opening, there were 32 injuries at Roppongi Hills related to revolving doors, but none was reported to police. They only became known after the boy was killed.

The Tokyo Metropolitan Police Department is investigating the boy's case with the intention of accusing senior officials of Mori Building and the door's manufacturer, Sanwa Tajima Corp., on suspicion of professional negligence resulting in death because it has learned the companies failed to take any safety measures.

Roppongi Hills, which opened April 25, 2003, is a popular business, shopping and entertainment complex. It had more than 49 million visitors in its first year.