Detention harm incidents spike expected

The immigration department is bracing for a potential spike in self-harm incidents at offshore detention centres in the lead up to Australia's federal election.

Department secretary Michael Pezzullo told a Senate estimates hearing in Canberra on Thursday night that there was a spike in incidents last year following Malcolm Turnbull's toppling of Tony Abbott as prime minister.

Mr Pezzullo blamed refugee activists for telling asylum seekers to hold out for a softening of tough border policies.

He said false hope from advocates was causing asylum seekers anxiety.

"No one is for a moment suggesting persons in Australia shouldn't exercise their democratic right to dissent (against government policies), but it needs to be done responsibly," he said.

Extra resources in health and mental health are being deployed to mitigate the risk, Mr Pezzullo said.

Mr Pezzullo acknowledged he had not seen any evidence of advocates specifically encouraging asylum seekers and refugees to self-harm.