A man was killed when a charging e-cigarette exploded and ignited oxygen equipment he is believed to have been using, Merseyside's fire service said.
The 62-year-old victim was found in the living room of a house in Penkett Road, Wallasey.
A small fire in the bedroom of the property had gone out before firefighters arrived, Merseyside Fire and Rescue Service (MFRS) said.
The exact cause of death is yet to be established, with an inquest now due.
An MFRS spokesman said: "The subsequent fire investigation identified that an e-cigarette that had been charging in the bedroom exploded, caught fire and ignited the oxygen tube of an oxygen concentrator, which may have been in use by the occupier."
Myles Platt, MFRS area manager said: "The investigation into the cause of this fire is continuing but at this stage it is thought that the charging device being used at the time may not have been the one supplied with the e-cigarette.
"We urge people to always use electrical equipment in accordance with the manufacturer's instructions and guidance, always ensure that no electrical items are left charging overnight or left unattended for a long period when being charged, and do not mix parts from different e-cigarettes.
"Only use the original charger or electrical cables supplied and ensure you purchase electrical items from a reputable source."
Since January, nine fires involving e-cigarettes have been recorded on Merseyside.
Service representatives are speaking to people in the Wallasey area to give advice about the safe use of e-cigarettes following Tuesday's fire.
8th August 2014