Riots rage in Mombasa, Kenya over killing of Muslim cleric Aboud Rogo Mohammed (VIDEO)

JOHANNESBURG, South Africa — Rioting continued for a second day in the Kenyan city of Mombasa, where Muslim youths angry over the killing of radical cleric Aboud Rogo Mohammed faced off with police.

A grenade thrown into a truck carrying security forces, sent in to quell the violence, left three police officers and a civilian dead and 16 other officers wounded, Reuters reported.

Hundreds of angry youths threw stones, barricaded roads with burning tires and looted shops in Kisauni, a predominantly Muslim area of Mombasa. Kenyan newspaper The Standard said Christian churches were vandalized again today, with at least one set on fire. 

Rogo, whom Washington accused of supporting an Al Qaeda-linked group in Somalia, was gunned down in his car Monday while driving with his family.

Images broadcast by Kenyan media showed his bloody corpse in the bullet-riddled car. His wife and children reportedly survived the attack.

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Kenyan Prime Minister Raila Odinga appealed for calm, saying the country should avoid an "inter-religious war."

"Let's act with restraint as law enforcement agencies get to the root of the matter," he told reporters, according to Kenya's Daily Nation. "We urge Muslims and Christians not to fight."

About 11 percent of Kenya's population is Muslim, or some 4.3 million people, most of them living along the Indian Ocean coast. Mombasa, a coastal city and Kenya's second-biggest, has a majority Muslim population.

Hotel owners in Mombasa told Reuters that the violence has hurt the tourism industry, a backbone of the city's economy.

As the riots raged, Somali militant group Al Shabaab called on Kenyan Muslims to "take all necessary measures" to protect their religion, and to boycott next year's presidential election.

"Muslims must take the matter into their own hands, stand united against the kuffar [non-Muslims] and take all necessary measures to protect their religion, their honor, their property and their lives from the enemies of Islam," said a statement from the group, which has ties to Al Qaeda.

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Rogo was on US and United Nations sanction lists for his alleged connection to Al Shabaab.

The UN Security Council imposed a travel ban and asset freeze on him last month, saying he had provided "financial, material, logistical or technical support" to the group.

Some Muslims in Mombasa have accused police of being behind the killing of Rogo, and human rights activists in Kenya say he is the fifth alleged Muslim extremist who has been killed or who disappeared in the last four months.

Police have denied involvement in the killing of Rogo.

Keriako Tobiko, the country's Director of Public Prosecutions, has set up a team to investigate the murder of Rogo, with findings due in 14 days, the Daily Nation reported

The team is to conduct a "comprehensive, independent and expeditious investigation into the murder with a view of apprehending and bringing to justice the perpetrators of the crime," Tobiko said in a statement.

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