Secretary of State John Kerry on Monday insisited the capture of an alleged Al-Qaeda operative in Libya in a daring US raid was legal, after Tripoli demanded answers about the "kidnap".
Abu Anas al-Libi, who was indicted in connection with the 1998 bombings of US embassies in Kenya and Tanzania and has a $5 million FBI bounty on his head, was captured on Saturday.
It was one of two US raids at the weekend, with US Navy Seals also storming a Shebab stronghold in the southern Somali port of Barawe, although the success of that assault was unclear.
The operation to capture Libi drew fury from the Libyan government, which said it was unauthorised and described it as a "kidnap".
But Kerry on Monday defended the operation as within the law.
"With respect to Abu Anas al-Libi, he is a key Al-Qaeda figure, and he is a legal and an appropriate target for the US military," Kerry told reporters on the sidelines of an Asia-Pacific Economic Cooperation (APEC) summit in Indonesia.
He added that Libi had committed "acts of terror" and had been "appropriately indicted by courts of law, by the legal process".
"The United States of America is going to do everything in its power that is legal and appropriate in order to enforce the law and protect our security," he said.
But when asked whether the United States had informed Libya before the raid, Kerry refused to say.
"We don't get into the specifics of our communications with a foreign government on any kind of operation of this kind," he said.
His defence of the operation came after Libya on Sunday demand an explanation from Washington for the "kidnap".
"The Libyan government has been following the reports of the kidnap of one of the Libyan citizens wanted by the authorities in the United States," a government statement said.
"As soon as it heard the reports, the Libyan government contacted the US authorities to demand an explanation."
Libi was taken to a US Navy warship in the region after the raid and was being questioned there, a US official said.
Libi, 49, had been indicted in the US federal court in New York for allegedly playing a key role in the east Africa bombings -- which left more than 200 dead -- and plots to attack US forces.
The Tripoli operation ended a 13-year manhunt for Libi, whose given name is Nazih Abdul Hamed al-Raghie. FBI and CIA agents assisted US troops in the raid, US media reported.
His arrest paves the way for his extradition to New York to face trial.
Citing surveillance camera footage, Libi's son, Abdullah al-Raghie, said his father had been seized by masked gunmen armed with pistols, and that some of them were Libyans.
He claimed that the Libyan government was implicated in his father's disappearance, a claim Tripoli vehemently denies.
Defense Secretary Chuck Hagel said Sunday the operations sent "a strong message to the world that the United States will spare no effort to hold terrorists accountable".
"We will continue to maintain relentless pressure on terrorist groups that threaten our people or our interests, and we will conduct direct action against them, if necessary, that is consistent with our laws and our values," he added.
Asked whether the abduction of Libi by US forces on foreign soil may send a negative perception about the United States to the world, Kerry insisted that should not be the case.
While the operation in Libya achieved its objective, it was unclear whether the Somalia raid on the beachfront villa of a leader of the country's Al-Qaeda-linked insurgents had been a success.
A US official said a "high-value" Shebab leader was the target but according to The New York Times, SEAL commandos were forced to withdraw before confirming the kill.
The target was a Kenyan of Somali origin known as Ikrimah, the Times reported Monday, citing an unnamed US official.
The strike follows last month's siege of an upscale shopping mall in the Kenyan capital Nairobi, where 67 people were killed, but Ikrimah, identified as a top Shebab planner, was not linked to that assault, the Times said.