Two police officers were fatally shot after stopping an automobile to identify its occupants in the US state of Mississippi, authorities said. Four suspects were later arrested.The incident took place on Saturday night when the officers stopped a Cadillac in an industrial park, the daily quoted an officer of the Mississippi Department of Public Safety as saying.Hours later, police arrested Curtis Banks, 26, and Joanie Calloway, 22, who face murder charges, and Marvin Banks, 29, taken into custody as an accomplice, said the mayor of Hattiesburg where the crime took place.A fourth suspect faces obstruction of justice charges.It is not yet clear why officers Benjamin Deen, 34, and Liquori Tate, 25, decided to stop the Cadillac, but one or more of the people inside opened fire on them, fatally wounding them.