Digha: The body of a nine-year-old girl sucked into the sea unnoticed by her father while he was removing sand from his trousers on the New Digha beach was washed ashore in Shankarpur, around 15km away, on Monday afternoon.

Police suspect Rousan Khatun had been swept away while walking or running towards her father Abu Ummar, who was then cleaning the bottom of his trousers.

Her mother Chandni Biwi and younger sister Fatema, 5, didn't notice anything either because they were around 20 metres away, East Midnapore police said.

The Digha outing was meant to be a day trip for the family of four from Anandapur, along the EM Bypass. They had travelled in Abu's car, which he uses as an app cab.

Rousan's death is the latest in a series of beachside tragedies in Digha and Mandarmani over the past two months.

The police said Rousan and her family had hit the beach around 3pm and frolicked on the edge of the water for a couple of hours. It was only when the little girl's parents realised she was missing that it occurred to anyone that a tide had come and swept her away, the police said.

"Abu had asked Rousan to go with her mother after he spotted some sand on his trousers and decided to wash it away. He possibly did not notice that Rousan followed him instead of going to her mother," an officer said, quoting the family.

Around 10 minutes went by before Abu walked back towards his wife and younger daughter, only to realise that Rousan was not with them. Chandni said she thought the elder of her two children was with her father.

The parents scoured the entire beach, teeming with tourists, for Rousan. They next went up to their car that was parked some distance away.

Abu reached Digha police station around 8pm to report that his daughter was missing from the beach. Teams from two police stations - Digha and Coastal Digha - searched for the girl throughout the night. "Since nobody saw her being swept away, we suspected she had lost her way. We even looked inside the dense cover of casuarinas near the beach," said an officer at Digha police station.

Around 5pm on Monday, villagers reported that the body of a girl had been washed ashore at Shankarpur. Digha police were informed and they took Abu and Chandni there to identify Rousan.

The body will be taken to Contai Subdivisional Hospital for a post-mortem on Tuesday.

The Digha-Shankarpur Development Authority recently clamped a ban on tourists venturing near the sea during high tide. A police officer said Rousan drowned during low tide.