The Turkish coast guard and maritime police vessels in Istanbul are searching for a Russian swimmer who went missing during a cross-Bosphorus race on Sunday, state-run media reported.

The swimmer, named by the Anadolu news agency as Nikolai Svechnikov failed to complete the 6.5 kilometre annual race from Istanbul's Asian shore to the European side.

According to information obtained by the police, Svechnikov arrived in Istanbul on Sunday and checked into a hotel in Beyoğlu.

While all participants in the race came ashore, police were informed that Svechnikov did not.

Competitors aboard a ferry heading to the start line of a 6.5-kilometer swimming race across the Bosphorus Strait, 24 August, 2025 More than 2,800 swimmers from 81 countries took part in Sunday morning’s competition, the 37th time it has been held, which is considered one of the world's leading open-water races.

Swimmers face strong currents and choppy waves while traversing the waterway, which links the Black Sea to the Sea of Marmara and divides Turkey's largest city.

The strait was closed to maritime traffic for the event, which is organised by the Turkish National Olympic Committee.

SwimTrek, a company offering entry to the race, describes race conditions as "challenging" on its website, adding that "experience of swimming in all sea conditions is essential."