Another four people injured in the explosion of a homemade explosive device at a St. Petersburg store on December 27 have applied for medical assistance, the city’s vice-governor, Anna Mityanina, said on Friday. The total number of injured now stands at 18, RIA Novosti reports. The previous evening, authorities reported 14 victims of what President Vladimir Putin described as a terrorist act. Eight of the people remain in hospital, according to officials.