He prayed for those missing in the incident.
Around 18 of the 40 people today went missing after a boat carrying them capsized on the Ganga river at Betawar ghat near Shooltankeshwar area under Rohania police station in Varanasi.
The boat, carrying 40 people who were going to Mirzapur from Varanasi, capsized on the Ganga river due strong flow of water in the afternoon.
Modi represents Varanasi in Lok Sabha.
"Prime Minister Narendra Modi has expressed his sadness over the capsizing of a boat in Varanasi district. He prays for those missing in the unfortunate incident," an official statement said here.