(a) A person is guilty of manslaughter in the first degree with a firearm when he commits manslaughter in the first degree as provided in section 53a-55 , and in the commission of such offense he uses, or is armed with and threatens the use of or displays or represents by his words or conduct that he possesses a pistol, revolver, shotgun, machine gun, rifle or other firearm. No person shall be found guilty of manslaughter in the first degree and manslaughter in the first degree with a firearm upon the same transaction but such person may be charged and prosecuted for both such offenses upon the same information.
(b) Manslaughter in the first degree with a firearm is a class B felony and any person found guilty under this section shall be sentenced to a term of imprisonment in accordance with subdivision (5) of section 53a-35a of which five years of the sentence imposed may not be suspended or reduced by the court.