Police in the North are investigating after a fire at a residential property in the Stream Street area of Newry.
The Police Service of Northern Ireland (PSNI) were notified of the fire by the Northern Ireland Fire & Rescue Service shortly after 4.40am on Sunday.
The force confirmed they believe "ignition was deliberate", adding that extensive damage was caused to the property and the fire had also caused a leak in an external gas pipe.
The PSNI described it as a "serious fire", adding the gas leak "threatened the lives of the residents of the property and their neighbours".
"Thankfully, they were all evacuated safely, but if our Fire Service colleagues had not acted so swiftly the consequences of this fire could have been catastrophic," a statement from the PSNI said.
Investigators are treating the incident as arson and are appealing for anyone with information to come forward.
