Security agencies at the Coast have been put on high alert following a midnight raid on a police post in Mombasa during which three of the attackers were killed.
Four of the raiders were also captured and are waiting to be charged in court.
Police said the gang of about 60 is believed to have been on a mission to steal weapons from Freretown police post.
Police said they donned red scarfs associated with a militia group known as Nyuki, which is sympathetic to the secessionist Mombasa Republican Council.
Nyuki Movement for Independence (NMI) is believed to be an off-shoot of the MRC.
Kisauni police boss Julius Wanjohi said: “After receiving a tip-off on the planned attack, police officers managed to mobilise themselves and repulse the youths, who were armed with bows and arrows, spears and machetes.
“After the attack, we managed to pursue them and three of them were shot dead,” Mr Wanjohi said.
The OCPD said four of the suspects who surrendered to the officers were arrested.
“We have interrogated them and they have informed us they belong to the Nyuki squad, which has similar agenda as MRC,” Mr Wanjohi said.
The suspects would be interrogated further to provide information on the real intention of the attacks, he said.
Kisimani community policing chairman Abdalla Abdulrahman said police were tipped off about the raid by the public.
“The group had already surrounded the station when members of the public informed officers. Luckily, the police managed to repulse the youths before they carried out their mission,” Mr Abdulrahman said.
Spent cartridges were yesterday scattered at the post, which is manned by 12 police officers.
One of the suspects said to have been the ring leader of the gang was shot at M’bungoni Village, a few metres from the post. Police found machetes, bows, arrows and red and black pieces of cloth in his house.
The residents accused the National Security Intelligence Service (NSIS) and local administrators of failing to inform the police on the criminal activities by the youths.
“The group has been meeting on the rooftop of a house, but we were shocked police did not get the information despite us informing local administrators,” a resident said.
Mr Wanjohi linked the group to a similar attack at Kiembeni Police Station last week in which an officer was injured in a petrol bomb attack.
The gang had walked into the police station at night under the pretext that they wanted to make a report.
However, the officer on duty grew suspicious of their intention and raised the alarm. His colleagues who responded to the distress calls arrived, but by then the attackers had vanished into the night.