Suspected Al-Shabaab men killed four police officers in an attack in northern Kenya, the latest in a series by the Somalia-based group linked to Al-Qaida, authorities and local residents said on Saturday.

The policemen were slain in a remote outpost of Garissa County bordering the war-ravaged Somalia on Friday evening.

The assailants raided the Galmagala administration police post, 10 km from the Somali border, at 7:30 p.m. local time and killed the four officers on duty. Dozens of local residents fled their homes in the attack.

Garissa County Commissioner Rashid Khatour on Saturday said the armed attackers numbering about 40 descended surprisingly on the police post. They also attacked others using guns, mortars and rocket-propelled grenades.

"Our officers managed to engage the bandits in fierce gun battle. However, the attackers were too big in number compared to our officers who were at the station at the time," Khatour said.

"After the attack subsided, four of our officers were found killed and another one vitally injured in the attack," said the administrator, who heads the County security.

He said the injured officer has been rushed to Garissa general hospital where he is undergoing treatment.

Dozens of people were scared by the deafening gun shots and bursts of the explosives thrown at the administration police post. They fled into the bushes and are being searched for by security personnel and local people, according to the official.

"Residents mainly children and women fled after hearing the earth shaking sounds of rocket-propelled grenades hurled at the police station, close to the center of the village," he said.

The security agency believes that the attackers are members of Al-Shabaab. "Their evil terrorist plans were thwarted by our gallant security men who fought hard despite been overwhelmed with weapons and number by their attackers," he added.

The administrator confirmed that part of the police post was destroyed by the raining mortar shells and rocket-propelled grenades.

In May, four security officers and two civilians were killed in a similar border incursion by Al-Shabaab fighters, who targeted the Abdi Sugow Administration police camp in Dadaab district.

The East African country's northern border areas have been hit by insecurity since October 2011, when the Kenya Defense Forces (KDF) launched a cross-border incursion into southern Somalia in pursuit of Al-Shabaab militants, who had kidnapped several foreigners on the side of Kenya along the border, posing a serious threat to the country's pillar industry of tourism.