ARMED police swooped on Malawi's seat of government in a dramatic show of force -- sparking fears of a major security incident at the heart of the nation's power.

Officers from the Police Mobile Service descended on Capital Hill in a police bus at around 11am, fanning out across both entry gates to stop and search vehicles going in and out of the sprawling government complex.

The operation -- which lasted about an hour -- sent onlookers into a spin, with many fearing something serious was afoot at the country's most sensitive government site.

But cops were quick to play down the drama.

National Police spokesperson Lael Chimtembo insisted the swoop was nothing more than a routine induction exercise.

"The officers are on site undergoing an induction exercise. That will be routine and people should not be surprised to see the officers. They are doing their work," she said.

Chimtembo added that the deployment was part of a wider push to beef up police visibility across Capital Hill, the City Centre and surrounding areas -- and to slash response times if a real emergency strikes.

But with officers checking every vehicle at both the main and secondary gates of one of Malawi's most heavily guarded sites, not everyone was convinced it was business as usual.

Police confirmed no specific incident prompted the operation.