The collision between the ships, Green valley and Tiger Singh, occurred at the confluence of the Hooghly and Rupnarayan rivers near Nurpur, South 24 Parganas Superintendent of Police L N Meena told PTI.
"One of the ships is badly damaged and it is sinking," he said.
Asked which ship was sinking, Meena said, "We cannot say right now."
"So far, there are no reports of any casualties. The police have rushed to the spot," Meena said.
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