MARINETTE, WI (WTAQ) - A chemical leak at a manufacturing plant forced the shutdown of Marinette Marine Tuesday.

Authorities say it happened just after 6 p.m. at ChemDesign Corp. 

The city of Marinette Fire Department/County Hazardous Materials Response Team arrived after some employees at Marinette Marine reported an odor.

Officials say that the chemical leaked was an ammonia based product.

Some Marinette Marine employees started to get headaches and became nauseous. The plant shut down and sent all second shift workers home early as a precaution.

No one needed medical treatment.

The leak was contained around 9:30 p.m. and the HAZMAT team conducted air monitoring of the buildings.

The cause of it is being investigated.