A federal judge struck down President Bush's authority to designate groups as terrorists, saying his post-Sept. 11 executive order was unconstitutionally vague, according to a ruling released Tuesday.

The Humanitarian Law Project had challenged Bush's order, which blocked all the assets of groups or individuals he named as "specially designated global terrorists" after the 2001 terrorist attacks.

"This law gave the president unfettered authority to create blacklists," said David Cole, a lawyer for the Washington, D.C.-based Center for Constitutional Rights that represented the group. "It was reminiscent of the McCarthy era."

The case centered on two groups, the Liberation Tigers, which seeks a separate homeland for the Tamil people in Sri Lanka, and Partiya Karkeran Kurdistan, a political organization representing the interests of Kurds in Turkey.

U.S. District Judge Audrey Collins enjoined the government from blocking the assets of the two groups. The same judge two years ago invalidated portions of the Patriot Act.

Both groups consider the Nov. 21 ruling a victory; both had been designated by the United States as foreign terrorist organizations.

Cole said the judge's ruling does not invalidate the hundreds of other designated terrorist groups on the list but "calls them into question."

Charles Miller, a spokesman for the U.S. Department of Justice, said, "We are currently reviewing the decision and we have made no determination what the government's next step will be."

A White House spokeswoman declined to immediately comment. At the time of his order creating the list, Bush declared that the "grave acts of terrorism" and the "continuing and immediate threat of future attacks" constituted a national emergency.

The judge's 45-page ruling was a reversal of her own tentative findings last July in which she indicated she would uphold wide powers asserted by Bush under an anti-terror financing law. She delayed her ruling then to allow more legal briefs to be filed.

She also struck down the provision in which Bush had authorized the secretary of the treasury to designate anyone who "assists, sponsors or provides services to" or is "otherwise associated with" a designated group.

However, she let stand sections of the order that penalize those who provide "services" to designated terrorist groups. She said such services would include the humanitarian aid and rights training proposed by the plaintiffs.

The Humanitarian Law Project planned to appeal that part of the ruling, Cole said.

"We are pleased the court rejected many of the constitutional arguments raised by the plaintiffs, including their challenge to the government's ban on providing services to terrorist organizations," Miller said Tuesday. "However, we believe the court erred in finding that certain other aspects of the executive order were unconstitutional."

The ruling was still considered a victory, Cole said.

"Even in fighting terrorism the president cannot be given a blank check to blacklist anyone he considers a bad guy or a bad group and you can't imply guilt by association," Cole said.

In 2004, Collins ruled that portions of the Patriot Act were too vague and, even after Congress amended the act in 2005, she ruled the provisions remained too vague to be understood by a person of average intelligence and were therefore unconstitutional.