HANOI -- Five people in a six-member family died last week in northern Vietnam after eating food suspected of containing rat poison, Reuters reported on Monday. An elderly couple and their daughter-in-law died on the way to a hospital in Bac Ninh Province, 40 km (24.84 miles) north of Hanoi, while the couple's son and a grandson died after being transferred to a hospital in Hanoi last Thursday, the *** Nguoi Lao Dong *** newspaper said. The newspaper quoted a doctor at the second hospital as saying the victims showed clear symptoms of consuming rat poison. The youngest grandson, who was six-years-old, survived the incident, the newspaper said, adding that authorities were investigating how the poison got into their food.