The new figures come as a growing number of crooks, armed with just a portable computer, use unsecured networks to make bomb threats, download pirated material and run online scams.

Their activities can leave unwitting netizens facing a lawsuit and even a police probe, said Mr Julian Ho, chief operating officer of Internet security firm ThinkSecure.

Read Chua Hian Hou's full story in Friday's edition of The Straits Times.