A Royal Navy bomb squad was called in and 40 homes were evacuated after a man died at a property in Devon yesterday.
Officers were called to Spencer Road in Newton Abbot at around 4.15pm on Monday following concerns for a man's welfare.
Devon and Cornwall Police said a 31-year-old local man was treated at the scene by paramedics but later died.
A 200m cordon was in place and a number of surrounding properties were evacuated, people were allowed to return to their homes in the early hours of this morning.
Specially trained officers remain at the scene to continue testing chemicals and items found in the property.
Police say there is no wider risk to the public.
A spokesman said: "While at the address a number of items were located which require expert analysis from specialist officers and the Royal Navy Explosive Ordnance Department."