In 1912, a Massachusetts law reduced the workweek by two hours. Lawrence mill owners in reduced the salaries of struggling workers to match. The pay reduction prompted one of the most effective labor strikes in U.S. history. Thousands of immigrant workers speaking 25 different languages joined forces and went on strike. The winter strike worsened living conditions for families. Attempts were made to relocate some of the children from Lawrence for their health and safety. Police used brutal force to prevent parents from putting their children on a train to Philadelphia. A Congressional investigation into conditions at the mills was launched and a delegation of child strikers from Lawrence testified in Washington D.C. As a result of their testimony, Congress pressured mill owners to accept the strikers’ demands.