BANGKOK: A 61-year-old Hungarian woman was killed and 22 other foreigners injured when their boat was hit by another vessel in Thailand's central Samut Songkhram province.The 30-seater boat was carrying 23 tourists to view fireflies at night along the Mae Klong river when another passenger boat with no passenger on board crashed into it, police said.The deceased was a Hungarian national along with 22 other passengers from South Korea.The crash took place about 500 metres away from the popular Amphawa Floating Market.The impact of the crash threw all passengers out of the boat.Local residents rushed to help them and alerted police, Bangkok Post reported.All passengers sustained injuries, but four of them were seriously hurt. They were all sent to nearby hospitals.Police believe that the boat driver might have turned off the lights so the tourists could clearly view fireflies in the dark night.The empty boat might not have seen the tourist boat when it crashed into it. The drivers of the two boats vanished after the crash.