A failed asylum seeker is under police guard in hospital after a deliberately lit fire on Manus Island caused significant damage to an accommodation block.
The blaze took 75 minutes to bring under control after it was started at Hillside Haus in Lorengau on Sunday afternoon.
Manus Island Police Commander David Yapu believes the consumption of alcohol was a contributing factor.
The suspect was taken to Lorengau General Hospital after cutting his hand when police went to arrest him on Monday.
Inspector Yapu expects the man will be charged with damaging properly and attempted arson when he is discharged from hospital.
"No one is above the law," the commander said in a statement.
Australian Border Force deputy commissioner Mandy Newton said early indications suggested the accommodation block was not destroyed, but the entire building was now unserviceable.
Ms Newton told a Senate estimates hearing on Monday night the fire had caused significant damage to electrics throughout the whole building, especially in the area of the kitchen facilities.
Nobody was injured in the blaze.
Detainees were offered alternative accommodation - predominantly at the East Lorengau Transit Centre - but the ABF said some men had refused to leave Hillside Haus.
Greens senator Nick McKim raised reports suggesting some men from Hillside Haus had gone to the transit centre on Sunday night but were turned away, with local police called to remove them.
Ms Newton said the reports were contrary to information provided to the department, with the ABF advised there was ample accommodation available at the transit centre.