A bipartisan group of U.S. lawmakers asked the Milwaukee Tool unit of Hong Kong-based Techtronic Industries to examine whether its products had links to forced labor, citing a recent media report that some were made by Chinese prisoners. In a letter sent Tuesday and signed by Republican Representative Chris Smith and Democratic Senator Jeff Merkley, the lawmakers questioned Milwaukee Tool's oversight of its supply chain and whether it had independently investigated the claims, according to a copy of the letter seen by Reuters.