A man has been arrested on suspicion of manslaughter after an explosion at an industrial unit left two people dead and another injured.
Police and the Health and Safety Executive are investigating after the incident in Hoddesdon, Hertfordshire, on the afternoon of 3 October.
Officers had been called by the ambulance service at 4.42pm to an industrial building on Plumpton Road. They were joined at the scene by the fire service and two air ambulances.
A Hertfordshire Police spokesman said: “Three men were taken to hospital.
“The two most seriously injured, a man in his forties and a man in his thirties from the Wood Green area of London, sadly died at Broomfield Hospital.
“The third man, who is in his twenties, was taken to Princess Alexandra Hospital in Harlow and has since been released.”
The scene remains cordoned off to allow specialist investigations to take place at the scene and establish the cause of the explosion.
A 40-year-old man from Hoddesdon has been arrested on suspicion of manslaughter by gross negligence and health and safety offences.