"Malawi is burning," read the Facebook chat from one of my African friends.

At least 18 anti-government demonstrators have been shot dead by police as riots convulse the small, tropical southern African country. More than 40 others have been hospitalized from the two days of disturbances in which thousands of demonstrators called for President Bingu wa Mutharika to leave office.

(More GlobalPost: Malawi president defiant as protest death toll rises to 18)

Mutharika denouced the protesters, saying they "are being led by Satan" in an angry speech over national radio Thursday that further inflamed the situation.

It seems the influence of the "Arab Spring" has reached from North Africa southwards to tropical Malawi and its riots are some of the biggest anti-government protests in sub-Saharan Africa this year.

The riots spanned the long sliver of Malawi, reaching from the southern tip, in the commercial center Blantyre, to the central capital, Lilongwe, to the northern city of Mzuzu.

This is somewhat surprising because Malawi has traditionally been one of the more orderly and peaceful countries in southern Africa. It was ruled for 33 years by Hastings Kamuzu Banda, from 1961 until 1994, and then the country managed the transition from one-party rule to multi-party democracy relatively peacefully. In my many visits to Malawi, I had always been impressed by the genial respect shown for political dialogue, from the man in the street to a cabinet minister.

But now the population is polarized and angered by the leadership of Mutharika and the once placid country is now combustible. It joins Swaziland, Uganda and Senegal as sub-Saharan African countries where anti-government riots have erupted.

Fuel shortages, rising prices and high unemployment built the popular dissatisfaction with Mutharika's govenment.

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The fierce crackdown in the normally peaceful nation is likely to intensify public anger against Mutharika. The campaign against him is led by a coalition of 80 groups which claim that Malawi is facing its worst shortages in 47 years of independence. They blame Mutharika for turning the country into an "autocratic kleptocracy."

Mutharika himself made the country's economic situation worse when he had a damaging public spat with the Britain, Malawi's former colonial ruler and its biggest donor, that resulted in the British government indefinitely suspending aid to the country.

The diplomatic row was over a WikiLeaks embassy cable in which Mutharika was referred to as "autocratic and intolerant of criticism." An enraged Mutharika expelled Britain's ambassador to Lilongwe. In response, Britain expelled Malawi's representative in London and suspended aid worth $550 million over the next four years, reported The Guardian.

Mutharika came to power in 2004 after working for the World Bank. He was re-elected in 2009 and has become increasingly intolerant of criticism.

In response to the new protests Mutharika took to the airwaves and warned that he would "ensure peace using any measure I can think of." He condemned the protesters, asking them: "If you break shops and banks, will you have fuel? You demonstrated yesterday and throughout the night until today, but is there fuel today because of the demonstrations? I think God will do something to help us, will bless us, because these people are not being led by God, they are being led by Satan."

Mutharika's words did not calm the situation. Protesters torched offices and vehicles of Mutharika's Democratic Progressive Party (DPP) on Thursday. Scores of shops owned by locals and foreigners were looted, including some owned by Chinese expatriates.

The police hit back hard, using live ammunition and killing at least four more people on Thursday. Rights activist Moses Mkandawire, director of the group Church and Society of the Protestant Church of Central Africa Presybeterian, said the victims would be buried on Friday, in a ceremony likely to ignite emotions.

"We are taking over the whole responsibility to bury our colleagues. The police are not doing anything," he said.

Malawian political analyst Noel Mbowela said events in Malawi show "people have been baptized and every time they see something bad, they will always go into the streets."

Malawi's health ministry spokesman Henry Chimbali confirmed 10 deaths in the northern cities of Karonga and Mzuzu, where protesters ransacked the offices of Mutharika's DPP party on Wednesday. The other fatalities were in the capital, Lilongwe, and the southern commercial hub of Blantyre after police and troops fired teargas to disperse crowds demanding that Mutharika quit.

"These figures are based on those casualties that are coming through to the hospitals," Chimbali told Reuters. "Some died in hospital, while some were brought by police already dead." A further 41 people were injured, six critically, he added.

Amnesty International called for an investigation into the killings. The human rights organization also said eight journalists were beaten by police during Wednesday's protests, and a female radio reporter was seriously wounded. Amnesty researcher Simeon Mawanza said the president's regime is becoming increasingly intolerant of dissenting voices.

"The tension there won't die down just because of yesterday's events," he told the Associated Press. "It could intensify, as people died at the hands of police."

Later Thursday the Mutharika government temporarily closed three FM radio stations. The stations were shut for five hours Thursday, after being warned to stop reports about the anti-government demonstrations.

The United States condemned the use of force in Malawi. The U.S. recently signed a $350 million aid package that is contingent upon respect for human rights.

Elections are not due again in Malawi until 2014, and Mutharika is barred from seeking a third term.

Malawi, which gained independence from Britain in 1964, is among the world's least developed nations and UNAIDS estimates there are 920,000 people living with HIV/AIDS.

Pop superstar Madonna has adopted two children from Malawi, and has tried to spearhead education projects in the country by building schools there. She said she hopes Malawi will find a peaceful way out of its troubles.

"I am deeply concerned about the violence today in Malawi, especially the devastating impact on Malawi's children," Madonna told AP. "Malawi must find a peaceful solution to these problems that allows donors to have confidence that their money will be used efficiently."

If the riots in Malawi continue and the country continues to burn, it could ignite fresh anti-government protests in neighboring African countries, such as Zimbabwe, Zambia. The "Arab Spring" may have an influence on sub-Saharan Africa, after all.

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