Kenya's President Uhuru Kenyatta has urged the opposition to avoid violent protests and take any complaints they have over last week's election to court.

Addressing the sporadic clashes that have erupted since his victory, Kenyatta also urged police on Monday to use restraint as they handled pockets of protest and anger.

Violence flared up before the announcement of the August 8 election were announced last week, largely between supporters of rival candidate, Raila Odinga, and the police.

"I truly believe there is no single Kenyan anywhere who wants to see violence, looting and demonstrations that end up destroying property," Kenyatta said.

"If there are those who feel aggrieved and they are not willing to accept, there are also constitutionally laid-down procedures."

Call for strike

Odinga called on people to stay away from work on Monday in protest at last week's result, but response to the call was limited with many businesses reopening after being closed during the tense election period.

Many shops opened up again in the capital, Nairobi, and in the western town of Kisumu for the first time in days, and cars and buses were moving around on streets that had been deserted even before the result was announced.

READ MORE: Relative calm in Kisumu after Kenya election clashes

The election commission declared President Uhuru Kenyatta winner by 1.4 million votes. International observers said the vote was largely fair and a parallel tally by domestic monitors supported the outcome.

But protests erupted in opposition-supporting pockets of Nairobi and in Kisumu, where defeated opposition leader Raila Odinga has strong support.

A Kenyan human rights group said 24 people were shot dead by police in the violence.

The police have put the number of dead at six and said those killed were armed criminals who attacked officers who were attempting to arrest them.

The Kenya Red Cross said on Saturday it had treated 93 injured people.