The United Nations Mission in Sierra Leone (UNAMSIL) was a United Nations peacekeeping operation in Sierra Leone from 1999 to 2006. It was created by the United Nations Security Council in October 1999 to help with the implementation of the Lomé Peace Accord, an agreement intended to end the Sierra Leonean civil war. UNAMSIL expanded in size several times in 2000 and 2001. It concluded its mandate at the end of 2005, the Security Council having declared that its mission was complete.
The mandate was notable for authorizing UNAMSIL to protect civilians under imminent threat of physical violence (albeit "within its capabilities and areas of deployment") - a return to a more proactive style of UN peacekeeping.
UNAMSIL replaced a previous mission, the United Nations Observer Mission in Sierra Leone (UNOMSIL).
According to Security Council Resolution 1270 of 22 October 1999 which established the operation, UNAMSIL had the following mandate:
- To cooperate with the Government of Sierra Leone and the other parties to the Peace Agreement in the implementation of the Agreement
- To assist the Government of Sierra Leone in the implementation of the disarmament, demobilization and reintegration plan
- To that end, to establish a presence at key locations throughout the territory of Sierra Leone, including at disarmament/reception centres and demobilization centres
- To ensure the security and freedom of movement of United Nations personnel
- To monitor adherence to the ceasefire in accordance with the ceasefire agreement (whose signing was witnessed by Jesse Jackson)
- To encourage the parties to create confidence-building mechanisms and support their functioning
- To facilitate the delivery of humanitarian assistance
- To support the operations of United Nations civilian officials, including the Special Representative of the Secretary-General and his staff, human rights officers and civil affairs officers
- To provide support, as requested, to the elections, which are to be held in accordance with the present constitution of Sierra Leone
In February 2000 the mandate had been revised to include the following tasks:
- To provide security at key locations and Government buildings, in particular in Freetown, important intersections and major airports, including Lungi airport
- To facilitate the free flow of people, goods and humanitarian assistance along specified thoroughfares
- To provide security in and at all sites of the disarmament, demobilization and reintegration programme
- To coordinate with and assist, the Sierra Leone law enforcement authorities in the discharge of their responsibilities
- To guard weapons, ammunition and other military equipment collected from ex-combatants and to assists in their subsequent disposal or destruction
Upon withdrawal, the remaining staff in Freetown were transferred to United Nations Integrated Office in Sierra Leone (UNIOSIL).