Police said they were thankful four people managed to escape an arson attack in Londonderry in the early hours of Tuesday.
The four - three women aged in their 60s, 50s and 20s and a man in his 30s - were in the Drumard Park home at the time of the attack.
Police said furniture was pushed up against the door and set alight, blocking an escape route. The residents were able to get out the back door.
A PSNI spokeswoman added: "Detectives are investigating an early morning arson attack in Derry-Londonderry.
"At around 3am police were alerted to a fire at a house in Drumard Park. It appears some old furniture was deliberately placed against the front door of the property and set alight, blocking the doorway.
"Thankfully all four residents inside were able to make their way out safely via the backdoor after being awoken by the smoke alarm however the front of the home was badly damaged by the blaze.
"A motive for the incident has not yet been established and we are keen to hear from anyone with information regarding this crime. The number to call is 101.”