France gradually granted more political rights and representation for the constituent territories of their two African federations, culminating in the granting of broad internal autonomy to each colony in 1958 within the framework of the French Community. Eventually, Chad gained full independence in August 1960, with Nigeria likewise declaring independence in October 1960, and thus their mutual frontier became an international one between two independent states. At a conference of the Lake Chad Basin states held in N'Djamena in December 1962 it was agreed to respect the existing boundaries within the lake. Since then the lake has decreased dramatically in size, and much if not all of the Chad–Nigeria border now runs over land, creating problems with border management and demarcation. In 1983 disputes between Chad and Nigeria over their mutual border escalated into fighting, after Nigeria sent troops to the area citing harassment of Nigerian fishers by Chadian elements, resulting in the deaths of 75 Chadian and nine Nigerian soldiers. In more recent years many thousands of refugees have crossed the border due to the ongoing Boko Haram insurgency in north-eastern Nigeria.