Five men have died after a wall collapsed at a recycling plant.
West Midlands Police said all five victims were pronounced dead at the scene of the industrial accident in the Nechells area of Birmingham.
Emergency crews were called to Hawkeswood Metal in Aston Church Road at 8.45am.
A sixth man was taken to hospital with serious leg injuries.
An investigation is under way and the Health and Safety Executive (HSE) has been notified.
Detective Superintendent Mark Payne said: "We are still in the very early stages of this investigation to determine exactly what happened this morning.
"Sadly five people have lost their lives and we have several teams of specialist officers supporting their families at this time.
"This has been a very traumatic incident for those who were at the site this morning and we will continue to work alongside the HSE and the other emergency services at the scene."
West Midlands Fire Service said a large concrete structure containing metal had collapsed at the site.
Two ambulances, an air ambulance, a hazardous area response team and an emergency planning officer were sent to the scene.
A West Midlands Ambulance Service spokesman said: "On arrival, ambulance crews found a wall that had collapsed.
"Sadly, there was nothing that could be done to save the five men who had been working next to it.
"A sixth man was partially trapped by the falling concrete but had managed to get out from the rubble himself.
"He was treated at the scene by ambulance staff and the doctor from the air ambulance for a broken leg before he was taken to Heartlands Hospital for further treatment."
West Midlands Fire Service deployed its Technical Rescue Unit (TRU) to the scene equipped with heavy lifting and cutting equipment.
Assistant Chief Fire Officer Gary Taylor said: "This is a devastating incident for everyone involved. Our thoughts and deepest sympathies are with the victims' families and colleagues.
"Once the police have finished their initial examination of the scene, our absolute priority will be to ensure that the bodies of those who have lost their lives are recovered in the most timely and safe way possible, and with the utmost dignity and respect."
Mr Taylor described the scene as extremely challenging, with a significant tonnage of concrete and metal, and a structure that is still unstable.
"We have an assertive recovery plan in place and expect this operation to take several hours," he said.
According to its company website, Hawkeswood Metal Recycling processes more than 500,000 tonnes of scrap metal each year.
The firm began trading more than 40 years ago and has a customer base that includes local authorities, major PLCs and smaller independent companies.