Italian authorities have launched an investigation into the deaths of 26 teenage girls whose bodies were discovered in the Mediterranean Sea on Sunday.

The victims are between the ages of 14 and 18 and are suspected to be natives of Nigeria and Niger who drowned while trying to cross the Mediterranean Sea from Libya to Italy.

Rescue workers found their bodies floating near a sinking rubber boat.

CNN reports that autopsies on the victims will be conducted on Tuesday. The police chief in the southern Italian city of Salerno told CNN that the coroners would investigate whether the young women had been tortured, sexually assaulted, or killed.

Libya is a popular destination for Nigerian and other West African migrants who use the North African country as a jumping-off point to travel to Europe by crossing the Mediterranean Sea.

In 2017 alone, at least 2,550 migrants have died trying to complete the treacherous journey to Europe.