Charges have been filed against the man accused of fatally shooting his estranged wife and taking off with the couple’s two young children. The incident sparked an Amber Alert earlier this week. The Markham Police Department reports that 40 year old Lynn Washington was charged with first-degree murder and parental abduction. He is accused of shooting his estranged wife, 27 year old Lakisha Roby early Wednesday morning at a gas station at in Markham. An autopsy Thursday determined Roby died of a gunshot wound to the back and her death was ruled a homicide. Authorities also believe he is responsible for the temporary disappearance of the couple’s two young children following the incident. The two toddlers went missing in the south suburbs, and an Amber Alert was issued hours after their mother was fatally shot. The two children turned up at the home of their father's mother in Harvey Thursday afternoon. Washington was taken into custody with incident on Friday.