Lawmakers introduced a pair of Senate bills on Thursday to combat the rising number of child labour violations in the United States, one targeting companies with federal contracts that employ children for more scrutiny and another increasing reporting requirements to Congress, reported Reuters.

A third bill, announced on Wednesday, seeks to improve protections for unaccompanied migrant children, including those who have ended up working in hazardous conditions in meatpacking plants and other factories.

US Democratic Senator Cory Booker from New Jersey and Republican Josh Hawley from Missouri are sponsoring a bill that would require companies, and their contractors, competing for federal contracts to disclose child labour and worker safety infractions or face penalties.

It would also require the Labour Department to compile a list of companies ineligible for federal contracts based on "serious, repeated, or pervasive violations of child labour laws."

It builds on an earlier legislative effort spearheaded by Booker's office that was focused on companies contracting with the US Department of Agriculture (USDA), which is a major buyer of meat and other foods for the National School Lunch Program and other government programs.

The Labor Department said earlier this month that in the 2023 fiscal year, which ended on Sept. 30, 2023, investigations had found close to 5,800 kids illegally employed in the US, an 88% increase from 2019.

Another bipartisan Senate bill introduced on Thursday by Republican Marco Rubio from Florida, with Democrats Alex Padilla from California and John Hickenlooper from Colorado, and Republican Roger Marshall from Kansas, would require the Labour Department to report more details to lawmakers about the perpetrators and victims involved in child labour cases.

The bill would require detailed, annual reports that include the age of children involved and any injuries or deaths on the job.

"US law needs to be strengthened to make sure these children are protected," Rubio said in a statement on Wednesday.

A February 2022 Reuters story exposed child labour at Alabama chicken plants, revealing how unaccompanied Central American migrants in debt to human smugglers were working gruelling factory shifts. Later, in November, the Labour Department filed a complaint against cleaning company Packers Sanitation Services Inc. (PSSI) for employing dozens of kids cleaning meatpacking plants around the country, some of whom suffered chemical burns and other injuries.

Reuters reporting last year also found migrant children, some as young as 12, were manufacturing car parts at suppliers to Korean auto giants Hyundai and Kia and more media coverage of the issue has followed.

Reuters coverage detailed how companies can rely on subcontractors, such as temporary staffing agencies, to recruit kids sometimes using false identity documents showing they are older. News organisations have also uncovered how some migrant children, after crossing the US-Mexico border alone, were released from federal custody and ended up working in dangerous conditions.

In a separate legislative effort announced Wednesday, a group of Democratic Senators, led by Senate Judiciary Committee Chair Dick Durbin from Illinois, introduced a bill to reform the government's care of unaccompanied migrant children.

Included in the proposal is a measure to increase access to visas for people who have been victims of crime or workers -- including children -- who have suffered or been witness to labour violations or cooperated with officials to investigate workplace abuse.