Suspected militia from Ethiopia on Thursday night killed three local people in the latest attack since the government ordered security crackdown in the restive town of Mandera.

Regional deputy police commander, Noor Gabow confirmed the incident on Friday, saying the armed militia attacked Malkamari village near the border with Ethiopia and shot dead two men and a woman.

"The militia crossed the border from Ethiopia and started shooting arbitrarily at the villagers and in the process killed two men and a woman. They later fled probably to Ethiopia," Gabow told Xinhua by telephone on Friday.

"We have launched investigations to establish the motive behind the attack but right now we can link it to local politics," Gabow said.

The latest killings came after Kenyan President Uhuru Kenyatta vowed to invest more resources in the security agencies to ensure the country is stable.

Speaking in Nairobi during a meeting with the country's top security chiefs on Thursday, Kenyatta said no effort will be spared in addressing security challenges which have engulfed the East African nation in the past three weeks.

"We will ensure police officers are sufficiently facilitated to enable them perform their duties effectively and in a dignified manner," Kenyatta said.

The Kenyan leader said he has already appointed a team tasked with the responsibility of identifying immediate priorities that need to be implemented in order to make the police service more proactive.

Criminal groups armed with crude weapons have been terrorizing residents of Bungoma and Busia counties in Western Kenya in the past two weeks, resulting into the death of over civilians.

Inter-ethnic clashes have also erupted in the northern Kenya town of Mandera which borders both Somalia and Ethiopia resulting in the death of four civilians and several injuries.

The killings have caused panic as the motive behind the arbitrary attacks is unknown. But police said investigations have been launched to establish the motive behind the attacks which has affected livelihoods and ordinary activities.

The latest killing has sparked tension which had subsided in Mandera which borders Somalia and Ethiopia following inter-tribal fighting that has claimed lives in the past two weeks.

Gabow said 18 guns and 665 rounds of ammunitions were surrendered as on Thursday in the going security operation in the clash torn Mandera County.

He said the firearms which include both heavy and light weapons were handed over to the security officers voluntarily by the warring clans of Degodia and Garre communities in bid take advantage of a government amnesty to surrender illicit firearms in the public hands.

Gabow said the firearms were surrendered by the both warring clans at their respective police station in response by the government to hand over illegal weapons in the hands of the communities living in the border County, which prone to inter-clan skirmishes'.

"People are responding well to the call by the government to surrender firearms wrongly in their hands as even as the operation to flush out armed gangs causing insecurity is underway in the County," Gabow said.

Gabow said sufficient security personnel among them the paramilitary officers and Rapid Deployment Unit (RDU) were deployed in the area to stop any further killings by the clan bandits.

Hostilities between the Garre and Degodia community have been building since the former lost their traditional Mandera central parliamentary seat to the latter in the last general election. Garre held the seat since independence.

Both Garre and Degodia have communal presence and have sophisticated armed militia in Ethiopia who has been used in clan fighting in the horn of Africa country.