Democrats in the House and Senate on Thursday introduced a bill aimed at cracking down on the illegal use of child labor, as regulators cite an increase in cases around the U.S.

The legislation, from Rep. Rosa DeLauro (Conn.) and Sens. Bob Casey (Pa.) and Patty Murray (Wash.), would ramp up fines for child labor violations and hold big corporations responsible for the actions of the smaller businesses they contract with.

The subcontracting provision is significant because the children working in name-brand meatpacking plants and other settings are often technically employed by outside companies, like cleaning contractors. Under current law, it is typically the subcontractor thats hit with fines.

Murray said in a statement that she was disturbed by reports of migrant children getting maimed in the workplace and called for real action at the federal level to crack down on illegal and exploitative child labor.

This is about protecting vulnerable children from exploitation and abusetheres no reason Congress shouldnt be able to act, she added.

The recent public concern around child labor stems largely from the investigative reporting of The New York Times Hannah Dreier. She published a series of stories documenting the dangerous work done by migrant children who left Latin American countries for the U.S. Many kids wound up performing hazardous duties in meatpacking plants, including cleaning heavy machinery.

A Labor Department official said earlier this year that the agency had seen a 50% increase in child labor violations since 2015. The cases came in two forms: children working more hours than were legally allowed for minors, or children performing hazardous tasks meant for adults, and sometimes getting injured.

We are seeing children who are being employed where they never should be in the first place, Jessica Looman, who runs the agencys Wage and Hour Division, said in February.