GENEVA (Reuters) - The death toll on the Mediterranean has nearly matched that of all last year, with more than 3,740 migrants and refugees having drowned on their way to Europe, and perilous winter months still to come, aid agencies said on Tuesday.

Migrants, who are part of a group intercepted aboard a dinghy off the coast in the Mediterranean sea, stand on a rescue boat upon arriving at a port in Malaga, southern Spain, October 22, 2016. REUTERS/Jon Nazca

Smugglers are now sending thousands of people on flimsy inflatable rafts from Libya to Italy in mass embarkations, perhaps to lower their own risks of being caught, but also complicating the work of rescue teams, they said.

At least 3,740 people have perished so far, nearly matching the death toll of 3,771 for all of 2015 when three times as many people, more than one million, took to the seas, the United Nations refugee agency said.

“This is by far the worse we ever have seen in the Mediterranean,” William Spindler, spokesman of the U.N. High Commissioner for Refugees (UNHCR), told a news briefing. “You could say that the death rate has increased three-fold.”

About 2,200 migrants were plucked to safety in the central Mediterranean in 21 rescue missions on Monday and 16 bodies were recovered, the Italian Coast Guard said.

At least 17 corpses from those weekend incidents are being brought to Italy, the International Organization for Migation (IOM) said.

“We were told by witnesses there may be many more. There may be other shipwrecks that occurred over the weekend that we’re learning more about,” IOM spokesman Joel Millman said.

Since the European Union-Turkey deal in March to close down pathways to Greece, the Libya to Italy route across the central Mediterranean has become the main route. One per every 47 migrants or refugees attempting the voyage between Libya and Italy is meeting is dying, the UNHCR’s Spindler said.

“Smuggling has become a big business, it’s being done almost on an industrial scale. So now they send several boats at the same time and that puts rescue services in difficulty because they need to rescue several thousand people on several hundred boats,” he said.

“But when you have so many people at sea on boats that are barely seaworthy, then the dangers obviously increase.”