BUCHAREST - Six children ranging in age from six months to seven years old and their father were apparently killed by carbon monoxide poisoning in Romania after an improvised heater malfunctioned, authorities said. Three girls and three boys were found dead on Monday, along with their 28-year-old father, in a studio apartment in the southwestern town of Rovinari, an emergency services spokesman told AFP. Forecasts called for temperatures around -5 degrees Celsius (23 degrees Fahrenheit) on Monday night. Dozens of people are sickened by carbon monoxide poisoning each year in Romania, one of the poorest countries in the European Union.