Annoyed by a recent wave of attacks against official US government Web sites, the White House this week warned hackers who targeted federal Internet sites that they would be caught and punished.

There's a government-wide effort to make sure that our computer systems remain secure," White House Press Secretary Mr Joe Lockhart said. "For those who think that this is some sort of sport, I think (it will be) less fun when the authorities do catch up with them ... and these people are prosecuted," he said.

Last week hackers responded to a six-state Federal Bureau of Investigation sweep of about 20 suspected hackers by attacking several government Internet locations, forcing the FBI, the Interior Department and the US Senate to temporarily shut down their Web sites.