The number of cases of politically motivated computer hacking increased in 2001, thanks mainly to political motivations (including ideological differences), criminal activity, disgruntled personnel and people after an intellectual challenge.

Dotcom (".com") domains accounted for nearly 30% (8,736) of all 30,388 web defacements in 2001. These include both US and non-geography specific global entities.

The latest figures, compiled by London-based IT company mi2g, show that several domains became "global hotspots" for defacement.

These included the ".cn" China domain and the ".tw" Taiwan domain, after the China-Taiwan standoffs and the US-China spy plane incident.

After ".com", they were the most defaced domains and together accounted for just under 9% (2,653) of total defacements for 2001.

The domain ".tw" rose by 1,178% to 1,355 from 106 and the ".cn" domain rose similarly by 1,326% to 1,298 from 91.

Mi2g chairman and chief executive DK Matai said: "Global web site defacement is indicative of the general conflicts prevalent in the physical world.

"2002 may be a year in which politically motivated attacks, both physical and electronic, could complement strikes from disgruntled employees and organised crime."

In the UK, the government domain ".gov.uk" experienced a 378% increase in web site defacements to 43 from 9 in 2000.

The UK organisations domain ".org.uk" rose to 25 from 5 and the UK commercial domain ".co.uk" increased by 181% to 385 from 137.

Mi2g said anti-capitalist protest, criminal activities and anti-NATO sentiment were principally behind the attacks.

The US government domain ".gov" experienced a 37% increase in web site defacements to 248 from 181 in 2000.

The US military domain ".mil" experienced a 128% increase in web site defacements.