Five whales who were floated back out to sea in the southern Indian state of Tamil Nadu have returned to the shore at Tuticorin. They were among the 36 whales who were rescued and pushed back into the sea on Tuesday. At least 45 whales died after more than 80 of the animals were stranded on the shore at Tuticorin. The last time such an incident occurred in Tuticorin, was in 1973 when 147 whales died. Local fishermen, helped by officials, used mechanised boats to float the stranded whales back into the sea on Tuesday, but five of the animals returned to the shore early on Wednesday, BBC Hindi's Imran Qureshi reports. "We were expecting [some of the whales] to return to the shore. We have again used boats to take them back into the sea," Dr Patterson Edward, director of the Tuticorin-based Sugandhi Devadasan Marine Research Institute, said. Scientists say they are unsure about the reasons behind the whales coming to the shore. "We can't say the exact reason. They could have come chasing a prey and lost their way," fisheries official A Srinivasan told BBC Hindi, according to a BBC online report.