A man suffered serious burns during an incident at an electrical sub-station in Staffordshire.
He was discovered lying in a road following reports of a loud bang and flash of light in Trentham, Stoke-on-Trent, on Thursday evening.
He was rushed to a burns unit in Birmingham with 55% burns. His condition on Friday was stable.
Police said it appeared someone had tried to break into the sub-station. It has been sealed off for examination.
Helicopter search
A spokesman for Staffordshire Police said they were investigating how the man, from Stoke-on-Trent, had sustained his injuries.
Reports of the bang came in from members of the public at around 23.30 BST.
"While officers were investigating a member of the public discovered a man lying in Trentham Road with severe injuries," he said.
A police helicopter was called out to search for any other casualties.