The bodies of 26 young Nigerian women and girls were retrieved from the Mediterranean Sea over the weekend and taken to Italy, where officials said on Tuesday they were investigating how the women died. “It is a tragedy for mankind,” said Salvatore Malfi, the prefect in the port city of Salerno, where the bodies arrived along with 400 migrants who were rescued in the central Mediterranean in recent days.

“I think prosecutors will start working soonest to evaluate whether it could be homicide,” he said in televised remarks, adding that autopsy results for the women could be released publicly in weeks. The young women were estimated to be between the ages of 14 and 18, said Marco Rotunno, the communications officer for the United Nations High Commissioner for Refugees in Italy. Their bodies were found floating in the water by the Spanish Navy on Friday, and survivors on nearby rubber dinghies, which had partly capsized, told the authorities that they were Nigerian and had departed from Libya.

Since the corpses arrived in Salerno on Sunday, no one has stepped forward to claim them as family members, Mr. Rotunno said. He said 400 migrants also landed on the same day. “So there was not a chance to speak with all of them, but probably they were not relatives of these girls,” he said. When such groups of young women and girls are alone, the probability is high that they are victims of sex trafficking rings, he said.