WASHINGTON - The capture of Ahmed Abu Khatallah, a Libyan whom Washington regards as a key suspect in the 2012 attack on an American Consulate in Benghazi, shows the United States will do ‘whatever it takes’ to find people who harm Americans and hold them to account, President Barack Obama has said.

‘We will continue our efforts to bring to justice those who were responsible for the Benghazi attacks,’ Obama said. ‘We will remain vigilant against all acts of terrorism, and we will continue to prioritize the protection of our service members and civilians overseas.’

In Tripoli, Libtan condemned US special forces’ arrest of Khatallah on the Libyan soil,  describing the action as a violation of Libyan sovereignty.

In the first official reaction from Tripoli, Justice Minister Saleh al-Marghani called for Khatallah’s return and stand trial in Libya. ‘We had no prior notification. We did not to expect the U.S. to upset our political scene,’ Marghani told a news conference. He said Khatalah had been wanted by Libyan authorities for questioning but a lack of security had prevented this. Said al Saoud, spokesman for the foreign ministry, said:’This attack on Libya sovereignty happened at a time when Benghazi is suffering from many problems.’ President Obama announced Tuesday that he’d authorized an operation on Sunday afternoon, Washington time, in which American special operators and law-enforcement agents arrested Khatallah. The suspect is now ‘in U.S. custody in a secure location outside of Libya,’ said Pentagon press secretary Rear Adm. John Kirby. ‘There were no civilian casualties related to this operation, and all U.S. personnel involved in the operation have safely departed Libya.’ Defence officials declined to provide additional details about the operation or the identity of the units or agencies that were involved. In a briefing, Kirby defended the amount of time it took to capture Khatallah, who has been said to live mostly in the open since the attack and has even given several interviews to reporters. The presumption in the question is that he was going to McDonald’s for milkshakes every Friday night and we could’ve just picked him up in a taxicab,’ Kirby said.

 These people actively evade capture. Putting yourself in a position where you can properly ID, and move against them takes a lot of planning. I don’t think anybody’s going to apologize for the effort over such a long period of time that eventually led to his capture.’

Attorney General Eric Holder said Khatallah faces three charges in the death of the U.S. ambassador to Libya, Christopher Stevens, and three other Americans ‘and we retain the option of adding additional charges in the coming days.’ He echoed Obama’s pledge to continue to pursue the Benghazi attackers.

‘Even as we begin the process of putting Khatallah on trial and seeking his conviction before a jury, our investigation will remain ongoing as we work to identify and arrest any co-conspirators,’ he added.

Other Cabinet members, including Defence Secretary Chuck Hagel and Secretary of State John Kerry, also hailed the capture and praised the troops, law enforcement agents and intelligence officers involved. Members of Congress, including those who have hammered the Obama administration over Benghazi, reacted cautiously to the news.

‘It is obviously good news that this terrorist is now in American custody,’ House Speaker John Boehner, a Republican, said, adding, ‘I am grateful for the work of our military - assisted by the FBI - in capturing him. I look forward to hearing more details regarding the raid, and I expect the administration to give our military professionals time to properly gather any useful intelligence he has.’

Senator Lindsey Graham, also a Republican, raised questions about how the administration plans to deal with Khatallah, arguing he should be held as a prisoner of war in the U.S. military prison at Guantanamo Bay, Cuba, rather than brought into the federal criminal justice system.