Protesters are demanding democratic reforms and accuse King Mswati III, who has ruled the tiny mountain nation for more than 30 years as an absolute monarch, of repression. Rights groups accuse the royal family, including the king's 15 wives, of enjoying a lavish lifestyle while many of the country’s 1.1 million people live in poverty.

Mbabane, the capital, and Mazini, the largest city, have reportedly been the most affected by the protests, which have seen demonstrators barricading roads and setting fires, often at businesses owned or linked to the royal family. Businesses, factories and trucks have also been reportedly burned in the industrial town of Matsapha.

The Eswatini government has imposed a nightly curfew from 6 p.m. to 4 a.m. to try to quell the demonstrations. Photographs and videos on social media show soldiers assaulting people believed to be protesters.

Activists have alleged that soldiers and police have killed more than 20 protesters since the protests began this week, but this has not been confirmed by police, government officials or health workers.

Acting Prime Minister Themba Masuku claimed that the legitimate protests had been "hijacked by criminal elements."

In a statement Thursday, South Africa’s department of international relations and cooperation said it noted "with great concern the ongoing political and security situation" in Eswatini. "We are particularly concerned by reports of loss of life and destruction of properties. The right to peaceful protest is universally recognized," said spokesperson Clayson Monyela. He called on Eswatini's security forces to "exercise total restraint and protect the lives and property of the people."

The protesters are demanding reforms that include lifting bans on opposition political parties, which have been outlawed since 1973.

Sonke Dube, president of the Swaziland Youth Congress which is involved in the demonstrations, called on the United Nations, the 16-nation Southern Africa Development Community and the African Union to intervene.

"We urge you to call Mswati to order. Isolate him from the community of peace-loving nations. Impose sanctions on him and his immediate family and cronies until we have a people’s government in Swaziland," Dube said in a statement.

South Africa’s ruling African National Congress (ANC), which has historical ties to Swaziland stretching from that country’s support for its liberation struggle, has criticized the government for violence against demonstrators. "The use of security forces to quell political dissent and the failure to address legitimate civilian concerns complicates the conflict and adds fuel to the fire," said ANC head of international relations Lindiwe Zulu.

The United States State Department Thursday upgraded its travel alert for Eswatini to warn Americans against any travel to the country and announced it would allow nonessential American diplomats and their families to leave due to the deteriorating security situation there.

"Eswatini is experiencing dangerous civil unrest and protests across the country," the department said, noting the imposition of a curfew, the closure of the international airport and communications disruptions. A day earlier, the department had urged Eswatini authorities "to exercise restraint and also maintain the utmost respect for human rights."

"As the situation continues to unfold, the U.S. urges all stakeholders in this situation to not only remain calm but also remain peaceful," deputy spokesperson Jalina Porter told reporters Wednesday.