( CNN ) -- A New Jersey law enforcement officer is charged with murder after police say he shot a man in an apparent road rage incident in Maryland , according to authorities . Joseph Walker , a sworn officer of the Hudson County prosecutor 's office , is accused of fatally shooting a motorist Saturday during an altercation off of Maryland 's Route 3 . The preliminary investigation suggests that two vehicles came to a stop on an exit ramp after a previous altercation . One of the drivers , Joseph Harvey Jr. , and a passenger then exited their vehicle and walked toward Walker 's , according to a news release from Maryland State Police . Walker , 40 , allegedly fired a .45 caliber Glock at Harvey and struck him . Harvey , 36 , died of his wounds Saturday night at Baltimore Washington Medical Center . Elena Russo , spokeswoman for the Maryland State Police , told CNN affiliate WJZ that Walker 's wife and three children were in his vehicle at the time of the shooting . Hudson County prosecutor 's office spokesman Gene Rubino says his office is aware of the fatal shooting involving one of its detectives , who was off-duty and traveling in Maryland with his wife and children . Rubino refused to comment further . It is unclear whether Walker has an attorney . Walker is facing second-degree murder and manslaughter charges . He is being held on a $ 1 million bond , Maryland State Police said .
Joseph Harvey Jr. , a Maryland detective , is charged with second -degree murder . CNN say he fatally shot driver Walker , after an altercation . Walker 's wife , kids were with him during the apparent road-rage incident , police say .