Nairobi: At least 36 people were killed Tuesday in an attack on a stone quarry in Kenya’s Mandera town by Al Shabaab militants even as President Uhuru Kenyatta vowed to intensify the war against terrorism.

According to officials, gunmen opened fire at the quarry after separating Muslims and non-Muslims, Al Jazeera reported.

The scene of the latest attack is about 30 km from the Nov 22 raid on a bus, in which 28 non-Muslims were separated from the Muslim travellers and were executed.

According to a Xinhua report, Kenyan police confirmed that at least 36 quarry workers were killed in the early morning attack in northern Kenya.

Mandera county police commander Noah Mwivanda said the workers were killed at 1 a.m. by a group of gunmen when they were sleeping at the quarry at Koromey, about 20 km from Mandera county bordering Somalia.

He said initial investigations have revealed that the militants were heavily armed.

The shooting at the quarry comes after an attack on a night club in the Kenyan town of Wajir Monday night.

One person was killed and at least 12 injured after gunmen hurled grenades and sprayed bullets at the building.

The Al Shabaab militants later Tuesday in a statement issued from the southern port city of Kismayo in Somalia owned the attack in Mandera county.

“In another successful operation carried out by the Mujahideen, nearly 40 Kenyan crusaders met their demise after a unit from the Saleh Nabhan brigade raided them in the midnight Monday at Koromey on the outskirts of Mandera,” Xinhua quoted Al Shabaab spokesman Sheikh Ali Mohamud Rage as saying in the statement.

The militants said the attack was part of a series planned and executed to serve as a response to Kenya’s occupation of Muslim lands and their ongoing atrocities against Muslims in the Kenya’s coastal city of Mombasa and Somalia.

President Kenyatta, addressing a news conference in Nairobi Tuesday, vowed to intensify the war against terrorism and said the East African nation would not relent in the war against the Al Qaida-allied terrorist group after the massacre in Mandera.

“This is a war against Kenya and Kenyans. It is not a war against the Jubilee Government or its leaders. It is a war that every one of us must fight. Our bickering only emboldens the enemy,” Xinhua quoted Kenyatta as saying during the televised news conference.

The president said Kenya has been subjected to a long history of murder and violence at the hand of bandits, terrorists and extremists for over two decades now.

He said Kenya has endured immense vulnerability owing to the collapse of the Somalian government in 1991 which led to civil war in that country, and provided space for bandits to roam the entire region.

The Kenyan leader noted that over 800 people, including the police, have been killed so far since the 1998 terrorist attack on the US embassy in Nairobi.

“More recently, there has been a series of terror attacks, culminating in the violence and murder at the Westgate Mall in September last year, and the murders early this morning in Mandera, ” he said.

“Today’s attack in Mandera targeted a soft area, leaving 36 Kenyans dead. The obvious intent is to create hostility and suspicion across ethnic and religious lines and to drive non-Muslims from certain parts of this country. The ultimate aim of this atrocious campaign is to establish an extremist caliphate in our region,” he said.

In a related development, Kenya’s police chief David Kimaiyo offered to retire Tuesday after serving for 34 years amid increased terror attacks across the East African nation.

Kimaiyo told a news conference in Nairobi that his retirement was a personal decision, and added that President Uhuru Kenyatta has accepted his resignation from the National Police Service.

“My retirement has been prompted by personal matters which I have discussed with the president, who has accepted my early retirement,” Kimaiyo told journalists in Nairobi.