Carlos Cruz and Devon Miller, who were arrested for their alleged involvement in the shooting death of Cruz's fiancée over the weekend, were expected to be formally charged with murder on Tuesday.Cruz, a Boston native, claims he was driving along Barrett Avenue in the Bronx with his fiancée, 18-year-old Chelsea Frazier, and the couple's 1-year-old son Sunday when the incident occurred. Cruz, 36, says they pulled the car over to tend to their son, Alijah, when they were attacked by an armed robber. Frazier was killed in the shooting, while Cruz suffered a bullet wound to his leg. The baby was not injured.However, police say the entire incident was staged, with 25-year-old Miller acting as the shooter. According to police, a witness heard Cruz yell to the gunman, "Wait, you forgot to shoot me," before hearing more gunfire.

Police say Frazier broke up with Cruz weeks ago, though the pair traveled to New York together to visit relatives.Authorities say Cruz has one prior arrest in Massachusetts and a sealed arrest in New York. Miller served four years in prison after a murder conviction.

Police say the couple's son is safe and is staying with relatives.

Child found unhurt at scene of fatal BX shooting