After around 50 people were stranded at the Sultangarh waterfall in Madhya Pradesh's Shivpuri district, police on Thursday said around 45 people have been rescued while six are still missing.The picnickers were stuck after the waterfall swelled suddenly on Wednesday. Thirty four people, who were standing on the river rocks got stuck, while 15 were washed away."The overnight rescue, which continued till 3 a.m. on Thursday managed to salvage 45 of those stranded on Independence Day. A missing report of six has been filed in Gwalior," Superintendent of Police Rajesh Hingarkar told IANS.The rescue teams, including the Border Security Force (BSF) and the National Disaster Response Force (NDRF), were sent several hours after the incident.The operation was stalled further till midnight due to heavy flow of water. It was only after the water receded that those stranded were taken out with the help of thick ropes.The Indian Air Force also saved five lives but the IAF helicopter could not continue its operation due to darkness.Madhya Pradesh Chief Minister Shivraj Singh Chouhan has thanked Union Home Minister Rajnath Singh and Defence Minister Nirmala Sitaraman for their help.