A home at the centre of an arson inquiry belongs to a "Teflon Don" who is serving a jail term for endangering life by setting fire to houses.
Firefighters and police were called to Shrewsbury Crescent in Humbledon just after 12.30am today after the blaze was reported.
A large hole can be seen in the front window of the living room, with the front panel of the door missing.
The Echo has been told by nearby residents that the house is Alan Smart's, who spent two decades terrorising people across Wearside as he acted as an underworld enforcer.
He had denied arson on December 23 and 24, both 2011, and he denied arson with intent to endanger life on April 29, 2012, but was convicted of all charges.
Judge Deborah Sherwin sentenced Smart to life imprisonment with a minimum tariff of seven-and-a-half years.
The court was told Smart was recruited by a "significant drug dealer" to set fire to a house in an effort to recover a £10,000 drugs debt from rap singer David Baker.
Smart set fire to the front door of a house and a car, before later setting fire to another house in Princess Road, where Baker and his partner Vicki Barnes had moved to in secret.
The blaze trapped Ms Barnes in her bedroom and she had to escape through a window, with the fire causing £60,000 damage to the house.
As the case concluded, Detective Inspector Dave English said: "Mr Smart had terrorised people, communities, and companies on Wearside and Tyneside for more than two decades.
"He was like the Teflon Don, and thought he was untouchable.
"A number of prosecutions against him over the years could not succeed due to witness difficulties.
"Even hardened, organised, criminals were frightened of him.
"That he is now starting a life sentence, and will be on licence for life whenever he is released, shows that he is not untouchable."
Anyone with information about this morning's fire can contact Northumbria Police on 101 or Crimestoppers anonymously on 0800 555 111 or via its website https://crimestoppers-uk.org/.