Two Kenyan police officers have been killed in an attack on a security post near the Somali border, with the suspicion falling on the same armed group behind the deadly siege at a Nairobi mall which left scores dead.
The attack early on Thursday took place in the town of Mandera. Regional police chief Charlton Mureithi said that in addition to the two police officers killed, three others were injured and 11 vehicles destroyed.
The attack came hours after the Somalia-based al-Shabab group threatened that violence would continue until Kenyan troops were withdrawn from Somalia.
The group's leader, Ahmed Godane Shaykh Mukhtar Abu Zubayr, warned the Kenyan public there was no way they could "withstand a war of attrition inside your own country", in a statement posted on the internet late on Wednesday.
"Make your choice today and withdraw all your forces,..." Godane said. "Otherwise be prepared for an abundance of blood that will be spilt in your country, economic downfall and displacement."
Westgate crime scene
Meanwhile, forensic experts from around the world, including the US, Britain and Germany, continued their work on Thursday at Nairobi's Westgate mall, carrying out fingerprint, DNA and ballistic analysis, said police spokesperson Gatiria Mboroki. She said she had no details on what the experts had found so far in the bullet-scarred, scorched mall and that their work was expected to take a week.
"We don’t even know the final death toll. It might be days before we know," Al Jazeera's Mohammed Adow reported from Nairobi. "This is a country in mourning."
At least 18 foreigners are now known to have died after al-Shabab fighters attacked the mall last Saturday, firing from automatic weapons and throwing grenades. They took many shoppers hostage and the siege lasted several days.
In addition to those killed at the mall, another 175 people were injured, including more than 60 who remain hospitalised.
Morgue officials in Nairobi have been preparing for a large influx of bodies still in the mall. Officials said that the shopping centre could hold dozens more bodies.
Authorities have said at least five al-Shabab attackers were killed and another 11 suspects have been taken into custody.
Washington is providing technical support and equipment to Kenyan security forces and medical responders, said US Ambassador Robert Godec. The US is assisting the investigation to bring the attack's organisers and perpetrators to justice, he said on Wednesday.