Former NFL player Sergio Brown has pleaded not guilty to charges of first-degree murder and concealing a homicide in the September death of his mother. Sergio Brown and his mother lived together in Maywood. Brown was arrested in San Diego on Oct. 10 after being deported from Mexico and extradited to Maywood two weeks later. He admitted going to Mexico with his mother's belongings, and prosecutors said he was using his mother's credit card in Mexico in the days after her death. Brown played football at Proviso East High School before his collegiate career at Notre Dame and professionally with the Patriots, Jaguars, Colts, and Bills.