ANGRY youths threw a grenade at a Kenyan police truck Tuesday, injuring 16 officers as riots rocked the port city of Mombasa for a second day after the killing of a radical Islamist cleric.A senior police official said two officers had been critically injuredin the grenade attack, which came as police tried to contain protests by hundreds of angry youths who threw stones, damaged cars and chanted slogans in support of slain preacher Aboud Rogo Mohammed.The cleric -- popularly known as Rogo -- was on US and UN sanctions lists for allegedly supporting Somalia’s Al-Qaeda-linked Shebab militants.He was killed Monday in Mombasa when unidentified gunmen opened fire on his vehicle as he was driving with his wife and children, leaving it riddled with bullets.Images released by his supporters showed his bloody corpse slumped behind the wheel. His wife and children reportedly survived the attack.Furious protests erupted in Mombasa after his death, with one person hacked to death, cars torched, businesses attacked and five churches looted or set on fire.As the rioting stretched into a second day Tuesday, the Shebab called on Kenyan Muslims to "take all necessary measures” to defend their religion."Muslims must take the matter into their own hands, stand united against the kuffar (unbelievers) and take all necessary measures to protect their religion, their honour, their property and their lives from the enemies of Islam,” the Islamist group said in a statement.Staff in Mombasa’s main hospital reported Tuesday that at least 14 people had been injured in the clashes, while two anti-riot police were also wounded apart from those hit by the grenade attack, police said.The Supreme Council of Muslims in Kenya condemned the violence, especially the targeting of churches."This kind of violence goes against our faith. The protesters shouldn’t hide behind Islam or any of its teachings,” said the council’s secretary general, Adan Wachu. "These are criminals and should be treated as such.”Rogo was the spiritual leader of the Muslim Youth Centre (MYC), a group viewed as a close ally of the extremist Shebab.The Islamist MYC blamed the authorities for what they called a "targeted assassination”, but police have dismissed the claim and say they are hunting the killers."Our beloved Sheikh Aboud Rogo... was murdered by the (unbelievers) as part of Kenya’s policy of extra-judicial killings against prominent Muslim activists,” the MYC said Tuesday in a statement.Police in turn blamed the killing on the Shebab, with police spokesman Charles Owino saying the group had sought "to galvanise support among the youth”."Rogo’s murder was a well-planned attack by members of Al-Shebab to gain sympathisers.... The Shebab have failed to get followers,” Owino told AFP.The preacher was placed on a US sanctions list in July for "engaging in acts that directly or indirectly threaten the peace, security or stability of Somalia”, specifically for recruiting and fundraising for the Shebab.The United Nations Security Council placed a travel ban and asset freeze on him in July, saying he had provided "financial, material, logistical or technical support to Al-Shebab”.