Firefighters worked throughout the night after a large fire broke out at an empty care home.
Emergency services were called to the disused Lunedale facility on Woodcock Drive in Platt Bridge at around 12.50am on Sunday after the blaze started on the first floor.
It took more than two and a half hours for fire crews to ensure the flames were fully out as the fire had spread through the roof.
A drone had to be used to survey the incident from the sky while firefighters wearing breathing apparatus tackled the blaze from inside and outside the building.
Police were called to the scene as it is suspected the blaze was started deliberately.
One fire engine remained at the scene on Sunday morning while waiting for building inspectors to arrive and assess the damage.
Crew manager Simon Doherty from Wigan fire station said: "It looks like someone's broken in and started a fire on the first floor.
"It was dealt with quite quickly. Nobody was in the building when we got there and it was all boarded up."
Around half a dozen fire engines in total went to the scene, with crews from Wigan, Hindley and Atherton all involved and a support unit also there.
The ambulance service attended as a precaution but was not needed.