Nine people have been arrested for trespassing following a protest at a recruitment agency in Auckland.
Auckland Action Against Poverty said Work and Income had been using Manpower Services to force beneficiaries into precarious work.
The group protested outside the company's central city office today, and six protesters locked themselves inside the office.
Group spokesman Jonathan King said the contracts beneficiaries signed had no pay rates, and did not specify where the work would be or what hours they would be expected to work.
Mr King said the contracts also asked for personal information such as religion and sexual preference.
"These contracts are illegal. The Ministry of Social Development (MSD) is making people accept these contracts with Manpower and threaten people that if they don't sign the contracts their benefits will be sanctioned.
"We want the ministry to stop collaborating with agencies like Manpower," Mr King said.
Police said nine people had been arrested for trespassing.
MSD regional director Lynda Smardon said it was confident Work and Income clients placed into work through the agency received job offers that complied with the ministry's criteria.
"We are aware of client concerns with Manpower's standard individual agreement. We understand Manpower have amended their individual agreement document.
"In addition to the individual agreement, clients receive and sign a Confirmation of Associate Job Brief document, which details their position, duration, location, hours and pay," Ms Smardon said.
She said 63 Work and Income clients had been placed into work through Manpower this year, and there had been no concerns or complaints raised by workers.