The White House won't deny reports claiming that it authorized the killing of an American citizen who is purportedly involved in planning al Qaeda attacks and is said to be hiding out in Yemen.

The New York Times and the Washington Post reported late Tuesday that Muslim cleric Anwar al-Awlaki was added to the CIA's list of alleged terrorists the US has targeted to kill. American forces have killed myriad suspected terror suspects using armed drone planes in Pakistan, Afghanistan and Yemen.

CBS News' Mark Knoller noted that the White House had issued no denial of the report by Wednesday morning. al-Awlaki was born in New Mexico and served for years as an imam in the United States. He has not been charged with a crime, but was linked by US officials to Maj. Nidal Malik Hasan, the psychiatrist alleged to have killed 13 at an Army base in Fort Hood and Nigerian Umar Farouk Abdulmutallab, the so-called "Christmas day" bomber who attempted to detonate a jetliner en route to Detroit.

"No WH denial to reports in NYT & WP that Obama Administration has authorized the targeting killing of American citizen tied to Al Qaeda," Knoller wrote on his Twitter feed.

The Times noted that the policy of killing Americans abroad is generally alien to US law.

"It is extremely rare, if not unprecedented, for an American to be approved for targeted killing, officials said," the Times' Scott Shane wrote. "A former senior legal official in the administration of George W. Bush said he did not know of any American who was approved for targeted killing under the former president."

Obama's Director of National Intelligence, Dennis Blair, announced in February that the United States may target its own citizens abroad for death if it believes they are associated with terrorist groups.

"We take direct action against terrorists in the intelligence community," Director of National Intelligence Dennis Blair told the House Intelligence Committee. He said US counter-terrorism officials may try to kill American citizens embroiled in extremist groups overseas with "specific permission" from higher up.

If "we think that direct action will involve killing an American, we get specific permission to do that," Blair said in response to questions from the panel's top Republican, Representative Pete Hoekstra.

Blair's comments came after The Washington Post reported that US President Barack Obama had embraced predecessor George W. Bush's policy of authorizing the killing of US citizens involved in terrorist activities overseas.

"After the Sept. 11, 2001, attacks, Bush gave the CIA, and later the military, authority to kill U.S. citizens abroad if strong evidence existed that an American was involved in organizing or carrying out terrorist actions against the United States or U.S. interests, military and intelligence officials said," the Post said. "The evidence has to meet a certain, defined threshold. The person, for instance, has to pose 'a continuing and imminent threat to U.S. persons and interests,' said one former intelligence official.

"The Obama administration has adopted the same stance. If a U.S. citizen joins al-Qaeda, 'it doesn't really change anything from the standpoint of whether we can target them,' said a senior administration official. 'They are then part of the enemy.'"

An earlier wrinkle in the US drone policy published in the Nation alleged that the US has used the security firm Blackwater in its targeted killing program, as part of a US effort to deny it has on the ground troops in that country.

With earlier reporting.