At least five people were Friday killed by suspected al-Shabaab militants at a construction site in Bodhei Majengo area, Lamu County.
A Chinese national was briefly detained by the attackers before being released.
According to police, the victims included workers constructing the highway leading from the Lamu Port to Ethiopia and South Sudan.
The attackers also destroyed a bridge that was under construction in the Majengo-Omolo area.
Police said the attackers had held hostage two Chinese foremen but they released them later.
A team of security agents who rushed to the scene did not find them. They had escaped into the expansive Boni Forest.
Police reports indicate that the militants were fleeing from security agencies who had been pursuing them since Thursday.
Lamu county commissioner Irungu Macharia said they are pursuing the attackers.
The bodies have been airlifted to the Manda navy base in Lamu.
The militants also torched two construction vehicles (tippers) and motorbikes belonging to the workers at the camp.
“We were working when one of my colleagues suddenly started shouting that he had seen terrorists. The militants appeared from nowhere and started shooting at us,” said Fred Menza, a survivor of the attack.
Additional security forces have since been deployed to pursue the militants.
Locals have also been asked to be on high alert and report any suspicious activities to the police.
Elders and religious leaders in the area have condemned the attack, describing it as an act of cowardice.
“It's cowardly to kill innocent, harmless people who are just going about their business. If they were men enough, they should have waited for the Kenyan soldiers instead of killing defenceless young men,” said Said Omar, a cleric.
It is the latest attack on the construction site in a series that have happened in the area despite ongoing security operations there.
The terrorists who seem to be getting some backing from locals aim to stall the construction of the key road which would open the area to many business opportunities.
They had in January this year attacked a site and burnt eight trucks. The LAPSSET Corridor Programme is Eastern Africa's largest and most ambitious infrastructure project bringing together Kenya, Ethiopia and South Sudan.
A Chinese company is constructing the road that will lead to Garissa, Isiolo and later to Ethiopia and South Sudan.
The road construction comprises of 257-km Lamu-Ijara-Garissa section which is part of the LAPSSET project as well as the Hindi-Bodhei-Basuba-Kiunga section which spans 113 km and the Ijara-Sangailu-Hulugho section which extends 83 km.
The LAPSSET has seven components that include construction of the Lamu Port at the Manda Bay; construction of railway line from Lamu to Isiolo (northern Kenya), Isiolo to South Sudan, and Isiolo to Ethiopia; construction of airports at Isiolo, Lamu and Lake Turkana and construction of the highway from Lamu to Isiolo, Isiolo to South Sudan, and Isiolo to Ethiopia.
Other components include construction of resort cities at Lamu, Isiolo and Lake Turkana; construction of an oil refinery at Lamu; and construction of an oil pipeline from Lamu to Isiolo, Isiolo to South Sudan, and Isiolo to Ethiopia.
The project is expected to promote regional socio-economic development along the transport corridor, especially in the Northern, Eastern, North-Eastern and Coastal parts of Kenya, areas considered as economically marginalized.
The attack came two days after Kenya Defence Forces operating in the area killed one militant and recovered an AK47 rifle with three magazines in Milimani area.
They are there under Operation Amani Boni which is meant to pacify the area and degrade the militants.
The area is among those under the dusk-to-dawn curfew and that explains why the attackers targeted the vehicles daytime.
The government has blamed ethnic profiling that is linked to political inclinations around elections, the looming voter registration drive and land disputes as the primary causes of the latest attacks and displacements in Lamu.
The area is near the Kenya-Somalia border which has been under attack by terrorists in the past.
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