In 2002, the 450 military observers, split in 95 teams, continued to monitor the Ceasefire along the ex-frontlines. The teams also investigated violations of the Ceasefire. Foreign troops continued to leave the country. The riverine units escorted the first ships on the Congo river, which was again open to commercial traffic. In June 2002 the UN troops' total number was 3804. Contingents from Ghana and Bolivia joined the force, of which more than a third of the soldiers were Uruguayan. More than a thousand soldiers were deployed in Kisangani. On 14 May 2002, a military observer died near Ikela following the explosion of a mine under his vehicle.