Authorities are investigating who took thousands of dollars’ worth of aluminum and copper from heating and cooling units belonging to a nonprofit group in Omaha.

Northeast Industries reported the damage to three industrial units last weekend. Employees discovered the missing material after noticing the units were blowing cold air.

Northeast Industries houses a vocational training center that helps nearly 35 people with intellectual disabilities. It will cost the nonprofit $30,000 to replace the units, though insurance will cover most of it.

The station reports Northeast Industries may install an alarm system with motion lights and video surveillance. But officials say it would be an added expense for their tight budget.