Belous was previously charged with assault and battery on a household or family member, and assault and battery causing serious bodily injury after Vainer was found dead inside a Lowell home on July 17.
An alleged gang member will appear before a judge Thursday to face charges in connection with the murder of a young Malden mother who was “caught in a hail of gunfire” while attending a concert in Everett where her boyfriend was performing in 2015.