A new U.S. congressional report says the United States cannot ensure that former detainees at the Guantanamo Bay military prison will not become involved in insurgent activities.

The report by the oversight panel of the Republican-led House Armed Services Committee says 27 percent of the 600 detainees transferred out of Guantanamo were confirmed or suspected to be presently or previously engaged in terrorist activities.

The report comes as the Obama administration is considering transferring some Taliban inmates from the prison to Qatar, in an effort to engage the Taliban in peace talks.

Democrats on the subcommittee called the report incomplete and issued a dissent.

The top Democrat on the subcommittee, Jim Cooper, said the report seems to be politically motivated and aimed at scaring Americans during an election year, instead of being a comprehensive, bipartisan look at former detainees.

REST OPT

Then-president George W. Bush set up the prison at the U.S. naval base in Cuba, after U.S.-led forces went to war in Afghanistan against the terrorists behind the September 11, 2001 attacks on the United States.

Last month, on the 10th anniversary of the prison's opening, United Nations human rights chief Navi Pillay voiced deep disappointment that the U.S. government has failed to close the facility, as President Obama pledged to do when he took office three years ago. Pillay said that prisoners remain arbitrarily detained indefinitely, in what she called a clear breach of international law.

In 2009, in one of his first acts as president, Mr. Obama promised to close the prison, but the efforts have been met with broad opposition from Congress, including on transferring prisoners from Guantanamo into the United States for trial or jailing.