Police said about 30 persons from Anandhanallur were proceeding in the van to attend a funeral when the van overturned due to slippery road conditions and fell into a channel.
P.Tailammal(60), V.Peramayee(45) and K.Alagammal(65) died on the spot, police said.
The injured were admitted to Hospital.
Carrying passengers in open van had been banned by the Madras High Court.However, people continued to use such vans as a mode of transport to distances within 20 km,local officials said.