MILAN (AP/WCMH) – The bodies of 26 female migrants who apparently drowned have arrived at the Italian port of Salerno as rescues intensify on the Mediterranean Sea, the U.N. refugee agency said.

The bodies were transferred to the Italian mainland aboard a Spanish naval ship carrying another 400 migrants rescued during four operations in the central Mediterranean.

Twenty-three of the dead girls were on a rubber dinghy that sank off Libya two days ago, Marco Rotunno, a spokesman in Italy for the U.N. High Commissioner for Refugees spokesman, said. Another 60 people were pulled to safety, but more may have perished at sea, Rotunno said.

The others died in a separate shipwreck.

CNN reported all of the victims were girls between 14 and 18. They are believed to be migrants from Niger and Nigeria.

Police say autopsies will be carried out on Tuesday. Coroners will be looking for evidence of torture or sexual abuse.

Humanitarian groups say some 2,500 migrants were picked up at sea over the last four or five days, making it the most intense period for rescues on the Mediterranean since Italy reached a deal with Libya this summer to slow departures of smugglers’ boats carrying migrants. In the same short and recent period, 37 bodies have been recovered, the Italian news agency ANSA said.

The number of migrants arriving in Italy so far this year is 30 percent lower than last year, 111,716 through Friday compared to nearly 160,000 in the same period of 2016, according to Interior Ministry figures.

The U.N.’s International Organization for Migration put the number of dead in the center Mediterranean route from Libya to Italy at over 2,600 through Nov. 1.