Palma emergency services were called to a gas leak at a home on Carrer Pisa just after 6am on 7 June, after 13 people were injured, four of them seriously.
According to SAMU 061, the seriously injured included a 34-year-old woman and three men aged 23 and 33. They were taken to Son Espases hospital.
The other nine people suffered minor injuries and were treated at the scene. When paramedics arrived, three people were found unconscious.
Multiple ambulances, police units and firefighters were sent to the address to deal with the incident and help those affected. The response involved SAMU 061, local police and the fire brigade.
Authorities are expected to look into the cause of the leak. For more Catalonia-wide news, see our news page.