Four workers killed last week while erecting a steel structure at an engineering site were asphyxiated, police say.
The men died on Friday while constructing foundations for a building at an offshore engineering firm's base in Great Yarmouth, Norfolk. Investigators think the structure at the Claxton Engineering site may have collapsed.
Post-mortem examinations showed all four died as a result of “asphyxia due to trauma”, police said.
Detectives, along with health and safety experts were investigating, and a report was being prepared for a coroner. Police said the inquiry would be “lengthy and complex”.
Two of the four men - named by police as Adam Taylor, 28, Peter Johnson, 41, Tom Hazelton, 26, and Dan Hazelton, 30 - were brothers.