The Montgomery County Police Department (MCPD) has announced that a 45-year-old Gaithersburg man has been arrested and charged with Negligent Manslaughter by Vehicle for a fatal July 20 collision on North Frederick Avenue, where he was speeding at nearly 98 mph and driving with a blood alcohol level almost twice the legal limit, resulting in the death of 39-year-old Isaac Akomanyi of Germantown.