Microsoft Corp on Thursday filed five civil lawsuits in Seattle, Washington against alleged malvertisers.

Malvertising is the term used to describe harmful online advertising and works by camouflaging malicious code as harmless online advertisements, Microsoft's associate general counsel Tim Cranton wrote in a blog.

The lawsuits allege that individuals using the business names Soft Solutions, Direct Ad,, ITmeter Inc and used malvertisements to distribute malicious software or present deceptive websites that peddled scareware to unsuspecting Internet users, he said.

Cranton added that names of specific individuals behind these activities were not known and the lawsuits were being filed to help uncover the people responsible.

(Reporting by Santosh Nadgir in Bangalore; Editing by Jon Loades-Carter)