The officers had been deployed to the restive northeastern region to take part in an operation against the Somali-led militants after two separate roadside bombs on Wednesday.
"The five police officers killed in the attack were headed to boost the ongoing operation in Liboi," said North Eastern regional coordinator Mohamud Ali Saleh referring to a town on the border with Somalia.
The Kenya Red Cross said the latest attack occurred between Malelei and Kulan in Garissa county when a vehicle hit an improvised explosive device (IED).
The blast flipped over the green police pickup and tore its rear end off.
The Shabaab, a Somali-led jihadist group linked to Al-Qaeda, claimed responsibility for the attack -- as well as for the previous two -- in a statement carried by the SITE Intelligence Group.
On Wednesday morning four police officers were killed when their vehicle drove over a roadside bomb near the Liboi border post.
Three were killed instantly and a fourth died of his injuries later, according to a police report seen Thursday by AFP that revised the initial toll of three.
Later in the day a convoy accompanying a local governor was struck, killing five officers including his bodyguard.
