A 14-year-old boy suffered back injuries on Sunday after becoming trapped beneath a wall that collapsed in Birmingham city centre.
The teenager was walking along Carrs Lane with his brother, opposite Marks & Spencer, at about 3.50pm when the 6ft by 3ft wall fell on top of him.
He was freed by the emergency services, including an Usar (urban search and rescue) paramedic trained to treat patients in hazardous areas or where access is difficult, and taken to Birmingham Children's Hospital for further treatment.
Some of the rubble landed in the road near a bus stop. It was pushed back on to the pavement by emergency services and a cordon placed around it.
Sgt Richard Wright said police were investigating whether the wall had been on land belonging to family gunmakers William Powell & Sons or the neighbouring Marks and Spencer staff car park.
He said: "At this time we are still investigating the cause, but it would appear that a member of the public - a 14-year-old boy - was subject to part of the concrete wall collapsing."
A West Midlands Ambulance spokesman said no one else was injured in the collapse.
The incident was not the first of its kind in Carrs Lane. In October 2004, an elderly woman suffered serious injuries after plunging 10ft down a hole that opened up in the pavement.
It later emerged the hole was caused by a previously unknown Victorian cellar that lay beneath the road.