Whoever, being armed with a dangerous weapon, enters a dwelling house and while therein assaults another with intent to commit a felony shall be punished by imprisonment in the state prison for life, or for a term of not less than ten years. No person imprisoned under this paragraph shall be eligible for parole in less than five years.
Whoever, being armed with a dangerous weapon defined as a firearm, as defined in section 121 of chapter 140, enters a dwelling house and while therein assaults another with intent to commit a felony shall be punished by imprisonment in the state prison for a term of not less than ten years. Such person shall not be eligible for parole prior to the expiration of ten years.