ROME (AP) — More than 1,400 migrants have been rescued from overcrowded vessels, including a sailboat, in four separate operations in the Mediterranean Sea off southern Italy, the Italian coast guard said Wednesday.

There were 47 migrants, including two children in immediate need of medical care, aboard the sailboat in distress off the region of Calabria, in the “toe” of the Italian peninsula, a coast guard statement said. They were rescued by a coast guard motorboat early Tuesday.

The statement said the rescues began late Monday night and ended in the early hours of Wednesday in the Ionian Sea off Calabria’s east coast. One coast guard vessel took on around 590 migrants from aboard a fishing boat, and then later brought on around 650 migrants from another fishing boat, the statement said.

A coast guard motorboat and an Italian border police ship came to the assistance of a fourth vessel, with 130 migrants aboard.

Authorities didn’t immediately give details on the nationalities of the passengers or routes taken by the migrant vessels. But generally, many boats with migrants sighted off the Ionian Sea set out from Turkey’s coast, where smugglers launch crowded and unseaworthy boats.

Earlier this year, a migrant boat navigating on that route slammed into a sandbank just off a Calabrian beach town and broke apart. At least 94 migrants perished and 80 others survived.

That shipwreck is under criminal investigation, including the role of several members of Italy’s border police corps, which operates vessels off the country’s long coastline. Four suspected smugglers have been arrested.

In addition, prosecutors want to know if rescue efforts could have been launched hours earlier. Italian border police boats reportedly turned back to port because of rough seas, and by the time a coast guard vessel, better equipped to navigate in poor sea conditions, reached the area, bodies were already in the water. In that case, the migrant boat had been spotted hours earlier by a surveillance aircraft operated by Frontex, the European Union’s border monitoring force.

Wednesday’s statement by the coast guard said that crew on a Frontex surveillance plane had spotted a fishing boat with the 590 migrants aboard. A Frontex patrol boat and a Frontex support vessel were among the assets involved in the rescue operations for the two fishing boats, according to the coast guard.

Alarm Phone, a nongovernmental organisation that frequently receives satellite calls from migrant vessels in distress and relays the information to maritime authorities in Italy and Malta, was among the organisations signalling the need for rescue for the 130 people aboard the fourth boat.