This is not my experience,it's my father's experience.
The story goes back to the time when he was in college approximately 30 to 32 years ago. He had a gang of his gregarious friends who roamed about the length of the place they resided. They were really young at that time, so obviously one likes to roam and explore at such an age.
One of the friends of my father told him that there is a fair after 2 villages... Approximately 20 kilometers from here. My father along with his gang of friends agreed to go to the fair as it happened only once an year and was very popular one.
It was rainy season at that time so one of my father's friends suggested that they should take a bicycle so if the street becomes floody they all remain together by holding on to bicycle. In those days the rural areas were not so developed and we did not have cemented roads in villages, it became really tough to cross streets in rainy season as they would all become covered with water and mud.
Now my father with his friends went to fair, enjoyed and started to return. It started to rain really heavily and before they knew it the streets were covered with water and mud. As was their idea to cross the area with their bicycle in water but 20 kilometers seemed really a very tough job. But in those days they didn't think it too hard and they were crossing the area chattering all the time. Night started to flow down and in rural areas people sleep early so it becomes really spooky to travel at night as you see no one near you.
Still they kept going. Suddenly they heard music like that coming from an orchestra. They turned and faintly saw a troupe of 4-5 people singing bhajan (local song sung during prayer). They thought they were people who do bhajans going on boat. They stared as their troupe came closer. As it approached them they were completely astonished. Those people were sitting on seaweeds joined together by threads...OMG... In no time they got it they were ghosts as the seaweeds cannot handle weight of 4 people. They didn't do anything, their troupe passed away and on the way back none of my father's friends or he himself talked. When they finally returned to their hostel room they talked that it was a weird and unforgettable experience.
When I heard this story I didn't believed it until I heard it from his friends too. My father is still in contact with his college Friends. Maybe the people of the troupe were doing bhajan when they drowned in flood that's why they did it when it was floody... Anything is possible.