Six people were killed on Wednesday in clashes between police and demonstrators who joined banned opposition protests against tax hikes, police officers told AFP.

After the violence, Interior Minister Kithure Kindiki issued a warning that the authorities would no longer tolerate it.

“Lives have been lost, scores of law enforcement officers and civilians have been grievously injured and unimaginable loss to the country’s economy has been occasioned,” he said in a statement condemning “widespread violence, looting and destruction of private and public property”.

“This culture of impunity will stop,” he vowed. Police had earlier fired tear gas on protesters in and around Nairobi, with five of the six deaths reported in the towns of Mlolongo and Kitengela on the capital’s outskirts.

Tear gas was also used to disperse crowds attacking a highway connecting Nairobi to the port city of Mombasa, with one death recorded in Emali, a town located along that route.

“We have three deaths in Mlolongo, where a group of demonstrators had blocked the road to protest, and we also have two others in Kitengela and one in Emali,” a police officer said.

“There was a confrontation with police officers deployed to quell the riots and some (people)… were shot in the process,” he said on condition of anonymity.

A second policeman said, “I can confirm the deaths in Mlolongo, Emali and Kitengela,” without elaborating further.

In Nairobi’s Kangemi slum, dozens of children were hospitalised, some unconscious, after teargas was fired near their classrooms, the head of the clinic told AFP.

“We took 53 of them to the hospital and they are all now in a stable condition awaiting discharge,” he said.

Opposition leader Raila Odinga, pursuing a protest campaign against the government, had urged demonstrations against a tax law that has seen fuel prices surge, adding to the difficulties faced by poor Kenyans.

But late Tuesday, police chief Japhet Koome said the authorities had not received any official notification of rallies, as required by law.

“All lawful means will be used to disperse such demonstrations,” he warned.  Major roads in several western cities where Odinga commands significant support were deserted as protesters took to the streets.