An inmate serving a federal prison sentence for murder has pleaded guilty to assaulting another prisoner with a sock stuffed with two padlocks. Patricia Brown pleaded guilty Tuesday in federal court in Hartford to assault with a dangerous weapon. Brown, 22, is already serving a 30-year sentence on a 2009 murder conviction in Minnesota, and she faces up to 10 years for the assault inside the prison. Federal prosecutors said Brown assaulted a fellow inmate at the Federal Correctional Institution in Danbury on May 4. The victim required stitches to close a wound near her ear and also suffered from headaches.