Irish Naval Service vessel the LÉ Eithne arrived at Taranto Port in Italy at about 8am on Monday after rescuing 399 migrants in the Mediterranean.
It was one of the busiest weekends so far this year for rescues in the Mediterranean, as people-smugglers took advantage of calm seas.
The Irish Naval Service was part of a rescue effort which also involved Italian, British and German ships.
Some 3,480 people were rescued on Saturday from 15 separate boats that set off from Libya, and 14 rescues were ongoing on Sunday.
The Irish Naval Service was involved in two operations which rescued 280 men, 78 women and 41 children.
The first rescue was at 8.45am on Saturday, when 310 migrants were saved from a barge about 48km north of Zuwarah, Libya after they had initiated a distress call.
The second rescue operation was at 5pm and involved two inflatable boats and 89 migrants about 70km north of Libya.
Saturday’s rescue was the sixth undertaken by the crew of the LÉ Eithne.
On Friday evening the crew picked up 105 migrants about 40km north of Tripoli, Libya.
Rescuing migrants
The Irish vessel will remain on standby in the Mediterranean for up to six months as part of the international community’s efforts to assist Italy in rescuing migrants attempting to sail there from North Africa.
During the first five months of this year, there were 46,500 sea arrivals in Italy, a 12 per cent increase on the same period of last year, the UN refugee agency said.
Italy’s government projects 200,000 will come this year, up from 170,000 in 2014.
The summer months are usually the busiest period for departures because the calm seas make the crossing easier.
This year growing anarchy in Libya - the last point on one of the main transit routes to Europe - is giving free hand to people smugglers who make an average of €80,000 euros from each boatload, according to an ongoing investigation by an Italian court.
It is estimated that more than 1,600 people have drowned so far this year trying to make the crossing.
Many are fleeing war in Libya, where Islamic State fighters are terrorising the population, fuelling instability in the war-torn country.
Additional reporting from agencies
