A boat with refugees and migrants arrives at Skala Sikaminias, on the Greek island of Lesbos, Greece, Feb. 29, 2020. (Xinhua/Marios Lolos)

French rescue services rescued 21 migrants in three operations Saturday after their bids to reach Britain floundered in the Channel, officials said in a statement.

Channel crossing attempts have increased since late 2018 despite the danger of heavy maritime traffic, strong currents and low water temperatures.

Four people suffering from severe hypothermia were plucked from the water a little past midnight Saturday after their craft capsized around two kilometers from the coast, maritime officials said.

An hour later, 13 migrants in an inflatable boat were rescued as they drifted north of Calais, and finally four more were plucked from an inflatable kayak by gendarmes near the port's shipping channel.

In 2019, 2,758 migrants were rescued by the French and British authorities while trying to make the crossing - four times more than in 2018, according to French officials.

The coronavirus pandemic has reinforced the trend, with the reduced number of trucks going through the Channel Tunnel leading migrants to opt for small boats instead.

AFP