Four people died, 10 police officers were injured and seven others were arrested in demonstrations called by opposition Nasa between October 2 and October 16, police have said.
Police spokesman George Kinoti also said Sh 6 million worth of property was lost when goons stormed Tumaini supermarket in Kisumu during the demonstrations on October 6.
Nasa supporters were protesting against the Independent Electoral and Boundaries Commission ahead of the October 26 repeat presidential poll.
Mr Mr Kinoti said police had taken stock of the destruction of property during demonstrations and warned that those found culpable would face full wrath of the law.
"We wish to inform the public that the police will endeavour to provide security throughout the country and ensure that those who wish to participate in the elections are accorded the space to exercise their democratic rights. Police will discharge their mandate in strict conformity with the law," he said.
Mr Kinoti added that in cases where lives were lost, inquests have began and promised to release the findings to the public.
He listed the incidents of breach of law recorded by police during the demonstrations:
On October 6, violent demonstrators barricaded roads to Kisumu city centre. Riotous mobs then raided Tumaini supermarket at the lake side city, where they stole and destroyed good worth Sh 6 million. Two of the supermarket employees were injured in the melee.
On October 9, violent demonstrators, some armed with knives marched along the streets of Nairobi. They attacked motorists along Uhuru Highway and snatched mobile phones from innocent pedestrians. Two police cars and seven private vehicles were damaged during the demonstrations.
On October 9, rioters threw stones at people at Kibuye market in Kisumu. Two refrigerators were stolen at Tiafa Park. Businessmen at Garissa Lodge also reported looting. The aggressor also smashed the windscreen of a police vehicle.
On October 11, demonstrations turned violent in Nairobi's city centre. Motorists reported to police that they vehicles were damaged.
On October 11, a crowd stormed the IEBC office in Kisumu before marching to the city centre. Two police officers and a pedestrian sustained injuries.
On October 11, demonstrations started peacefully but turned chaotic in Homa Bay town. The rioters snatched a firearm from a police officer and threw it in a shed which they set ablaze. The mobs also threw stones at Homa Bay police station. Parts of the station were damaged and a civilian member of staff was injured.
On October 13, rioters threw stones at Kondele and Nyalenda police stations. Two police officers suffered injuries. The demonstrators later looted goods from a nearby wholesale shop before setting it ablaze. Managers at Rarieda hotel also reported losses.
On October 13, looting incidents were reported in Bondo. Three people died and a police officer was injured in confrontations that followed between looters and police. Demonstrators hurled stones at police using catapults.
On October 13, demonstrators barricaded Migori-Awendo Road. Motorists were forced to part with money before being allowed past the illegal roadblocks. When police intervened, the demonstrators threw stones and a police car was damaged. A police officer was also injured.
On October 17, IEBC officials were injured after being attacked by demonstrators in separate incidents at Awasi in Kisumu, Siaya and Vihiga.