At least three people were on Monday killed in a blast in a food kiosk outside Mandera police station.
Police said the blast was caused by an Improvised Explosive Device that had been planted in the hotel and was set off as a crowd sat for food.
The security officers said the IED had been planted on Sunday night to target those frequenting the area.
Among those killed were two police officers and a female civilian. Police said the woman was the owner of a hotel which was affected.
Police who responded to the scene said almost 20 people were injured in the blast.
It comes as the area has been experiencing a lull in attacks from the al Shabaab terror group. Security officials said the bomb was set up by the militants.
On Sunday, at least two members of the National Police Reserve (NPR) were killed in an attack by suspected terrorists in Witu, Lamu County.
Police said another reservist was injured in the attack on Saturday night. The attackers also burnt a house and a motorcycle before stealing foodstuff.
Witnesses said the victims were shot and killed after a battle.
The survivor had a bullet wound in the leg.
The attack happened in Ziwa la Taa village in Witu, police said. This is the latest attack in the area even as officials link the trend to land disputes in the fertile stretch.
The attacks have left many dead and displaced hence affecting development.
Kenyan special forces staged an ambush on an al Shabaab temporary camp near the Kenya border past Hagardera refugee camp.
Officials said two al Shabaab fighters were critically injured but managed to escape.
The al Shabaab members were planning to lay an IED when they were ambushed on Sunday, March 24 morning.
During the successful operation, the team recovered Improvised Explosive Devices (IED) making materials, an AK47 rifle, two magazines, porches and assorted foodstuffs.
The area is near the Kenya- Somalia border where the terrorists cross and launch attacks inland.
