A U.N. peacekeeper stands guard as women walk into a civilian shelter at the U.N. compound in Malakal, South Sudan, on July 13, 2016. (Jane Hahn/For The Washington Post)

The U.N. Security Council voted Friday to strengthen its peacekeeping mission in South Sudan, where an outbreak of violence has sparked concerns about a resumption of civil war.

An additional 4,000 peacekeepers will be dispatched, making the total deployment 17,000 troops, and U.N. forces will be asked to take more “proactive” measures to protect civilians.

The vote came as the United Nations is facing criticism over its failure to protect South Sudanese civilians and to use appropriate force when its installations come under fire, as they did in the capital city, Juba, last month.

The U.N. mission was established in South Sudan in 2011 after it voted to secede from Sudan. At the time, the mission’s primary goals were “state building and economic development,” according to its original charter.

South Sudan on Wednesday rejected a U.S. proposal for the U.N. Security Council to send 4,000 additional troops to the East African country to restore calm. (Jason Patinkin/AP)

But in late 2013, when the country descended into civil war, prompted by a split between President Salva Kiir and Vice President Riek Machar, the U.N. mission’s responsibilities changed dramatically.

Almost overnight, tens of thousands of civilians rushed to U.N. compounds, and peacekeepers found themselves trying to keep them safe in makeshift displacement camps across the country. U.N. officials initially considered the turmoil a temporary problem. It was not. Two and a half years later, 180,000 people live in U.N. shelters.

A peace deal signed last year was supposed to stop the fighting, but it fell apart last month when fighting flared in the capital between Kiir’s and Machar’s forces, leaving hundreds dead. During that violence, two U.N. compounds in Juba came under fire. Two Chinese peacekeepers and 11 civilians were killed, and 139 people were wounded in and around the U.N. base. Dozens of women reportedly were raped by members of South Sudan’s security forces.

It was proof, some observers said, that the United Nations needed a more robust force and mandate that would give it the power to intervene with lethal force to restore peace in the country. That is what the Security Council approved Friday. The 4,000 additional troops come from a regional African protection force belonging to the eight-country Intergovernmental Authority on Development.

Peacekeepers are not traditionally used in offensive operations, and it remains unclear what their new mandate means in practice and how it will differ from the current mission.

The South Sudanese government has expressed opposition to the expansion to the U.N. expanded mission. During and after the most recent clashes, government forces have restricted the movement of humanitarian workers, even looting a World Food Program warehouse holding rations that would have fed 220,000 people for a month. It is rare for government forces themselves to be among the hostile actors that peacekeepers are sent to pacify.

The council did not vote on whether to impose an arms embargo on South Sudan, as the head of U.N. peacekeeping forces, Hervé Ladsous, has urged.

Last week, the United Nations released a report on an investigation into an attack by South Sudanese soldiers and their allies in February on a U.N. camp for displaced civilians in Malakal in South Sudan. Dozens of civilians in the camp were killed. Peacekeepers there failed because of a “combination of inaction, abandonment of post and refusal to engage,” the inquiry found.