U.S. warplanes carried out airstrikes against fighters linked to Islamic State in Iraq and the Levant (ISIL) in western Libya on Friday, killing as many as 40 people in an operation targeting a suspect linked to two deadly attacks last year in neighboring Tunisia.
It was the second U.S. airstrike in three months against ISIL in Libya, where the group has exploited years of chaos following Muammar Gaddafi's 2011 overthrow to build up a presence on the southern shores of the Mediterranean Sea.
A senior Pentagon official confirmed to Al Jazeera that the most recent airstrike, which took place in the early hours of Friday morning, hit an ISIL training camp near Sabratha, Libya. The official said the strike likely killed ISIL operative Noureddine Chouchane.
Tunisian security sources have said they believe Tunisian ISIL fighters have been trained in camps near Sabratha, which is close to the Tunisian border.
Chouchane is believed to be connected to the attacks last year on a Tunis museum and the Sousse beach resort which killed dozens of people.
Officials have said those two attacks, both claimed by ISIL, were carried out by gunmen who trained in Libya.
"We are assessing the results of the operation," said Col. Mark Cheadle, spokesman for the Pentagon's Africa Command.
Sabratha Mayor Hussein al-Thwadi said officials visited the site of the strike and found weapons in the targeted building. Some Tunisians, a Jordanian and two women were among the dead, he said, and several Tunisians who had recently arrived in Sabratha were among survivors. He gave no further details.
Since Gaddafi was overthrown five years ago, Libya has slipped deeper into chaos with two rival governments each backed by competing factions of former rebel brigades.
As ISIL has expanded in the North African country, taking over the city of Sirte and attacking oil ports, calls have increased for a swift Western response to stop the group establishing itself outside its territory in Iraq and Syria.
Western officials and diplomats have said airstrikes and special forces operations are possible as well as an Italian-led "security stabilization" plan of training and advising.
U.S. and European officials insist Libyans must invite help through a united government, but say they may still carry out unilateral action if needed.
Last November the United States said it carried out an airstrike on Libya's Derna to target Abu Nabil, also known as Wissam Najm Abd Zayd al Zubaydi, an Iraqi commander in ISIL.
Al Jazeera and Reuters