Beijing, Oct 25 : Fourteen people were killed and over 145 others injured following a powerful explosion at the site of prefabricated houses in China s Shaanxi province. The explosion hit five prefabricated houses around on Monday, damaging nearby buildings at Xinmin township, Xinhua news agency reported. Among the injured, 106 remain hospitalised and 41 have returned home following treatment, according to authorities on Tuesday. Rescue efforts concluded as of 9 a.m. on Tuesday.An initial investigation indicated that the explosion could be caused by explosives. The makeshift houses were built inside a residential compound. The explosion also damaged 58 nearby houses and 63 cars. The prefab houses, owned by a local villager, were rented out in September. The owner of the houses is in police custody and an investigation is under way. All people in the affected area were evacuated.