Four members of a family, including a couple and two children, were burnt to ashes, when their house caught fire last night, at Rajulakandriga village of Yerpedu mandal in Chittoor district. All the four are said to become unconscious, due to spreading of gas in the bedroom, from a cylinder that leaked. Consequently, the house caught fire, Police said. Neighbours said that by the time they noticed, all the four were burnt to death. The family is said to have taken the house for rent recently.