STOCKHOLM  - Sweden`s crisis management agency on Sunday urged state bodies to ensure their Web sites could withstand attack after news reports said hackers had shut down several official Internet sites.

The furore began after police on Wednesday shut down the Pirate Bay site, which the international recording industry says is a major source for downloading pirated music and films.

A day after the raid, the police force`s own Web site went down. The main government Web site went off line in the early hours of Sunday.

Local media said hackers attacked the sites, now functioning again, after the clampdown on Pirate Bay.

``We are responsible on a government level for IT security in Sweden, we have to see why has this happened and what can society do about it,`` Steffan Karlsson, head of the Emergency Management Agency.

His agency urged all 31 bodies involved in emergency management, such as the police and rescue services, and all 21 local authorities to ensure they were safe from attacks on their Web sites, which are sources of information in a crisis.

Karlsson said he did not know what caused the government Web site to close, although the newspaper Aftonbladet quoted a group called World Wide Hackers as saying they had arranged an attack on it.

Sweden last year banned the downloading of copyright protected music and movies from the Internet after being singled out for criticism by Hollywood. The raid on Pirate Bay was the latest of several actions against suspected online piracy.

Critics, often young and technically savvy, have said the police are heavy handed and that people should have access to free information via the Internet, including file sharing.
Several hundred people demonstrated in Stockholm on Saturday in support of Pirate Bay, which is open again. Critics of file-sharers say they are just interested in free access to music and movies rather than in freedom of information.

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