Turkish authorities have arrested four suspected human traffickers over the deaths of 12 Syrian migrants in two boat sinkings the day earlier, including a 3-year-old boy whose image became a viral symbol of the tragedy of refugees, a report said Thursday.

The four, all Syrian nationals aged between 30 and 41, are accused of "causing the death of more than one person" and "trafficking migrants", the Dogan news agency reported. They are to appear in court later Thursday.