Case management staff working with refugees on Manus Island have been forced to leave the island by angry landowners.

Key points: Case management staff were told to leave after a protest at one of the accommodation centres yesterday

Case management staff were told to leave after a protest at one of the accommodation centres yesterday Police commander David Yapu said the protest was by landowners linked to the company Peren Investments

Police commander David Yapu said the protest was by landowners linked to the company Peren Investments He said the dispute was over "the awarding of the contract for case management"

Police on the island say 10 staff from the company JDA Wokman, which is contracted to provide case management and resettlement services, have been told to leave for their own safety after a protest at one of the refugee accommodation centres yesterday.

The protesters blocked access to the East Lorengau Refugee Transit Centre and demanded that a landowner company be given the case management contract.

Refugees said the protesters stopped medical staff from entering the accommodation and treating patients for several hours.

Manus Province police commander, David Yapu, said the protest was by landowners linked to the company Peren Investments.

"Because the situation was tense and level of threats was high, Police intervened and acted as a middle person to negotiate with PNG Immigration and Citizenship Service Authority, Peren Investments and JDA [Wokman] to come to some mutual understanding and clear the road block and allow the services to flow into the centre," he said.

"The issue behind the road block was about the awarding of the contract for the case management."

Chief Inspector Yapu said police were eventually able to clear the road and were watching for further unrest.

"The road block was cleared and and normal services restored," he said.

"I have instructed our Mobile Squad to patrol and monitor the situation on ground at East Lorengau Transit Centre from time to time."

JDA Wokman referred inquiries to the Australian Department of Immigration and Border Protection.

The ABC also contacted PNG's Immigration and Citizenship Service Authority, which did not respond.