A GSU officer stationed at State House Gate D in Nairobi has died after a man armed with a spear launched an unprovoked attack, killing him.

The assailant was quickly subdued and arrested and taken to police custody.

Police say a man claimed to have been sent by Satan to attack the officer.

The motive behind the brazen mid-morning assault remains unclear, though detectives from multiple security agencies are probing whether the suspect had any prior links to the slain officer or if the attack was random.