The head of Libya's air force, Brigadier General Saqr al Jarushi, told BuzzFeed News that as of Monday evening, the death toll in the air strikes had risen to 150.
"Today, the official numbers stand at 150 terrorists killed," he said, when reached by telephone in Tobruk, Libya. "The Egyptian air force hit four different targets in Darna."
He said that the Libyan military had assisted the Egyptian air force by giving them target points and maps pinpointing the location of ISIS militants.
"Darna was kidnapped by terrorists and we helped them, the Egyptian army, to free it," said Jarushi, who added that there was an "open line of communication" between the Libyan air force and the Egyptian air force.
The airstrikes, he said, had to be conducted carefully as it was believed that ISIS had anti-aircraft weaponry.
Egypt's air force launched airstrikes against ISIS targets in Libya overnight, in reaction to a grisly video released by ISIS Sunday showing the group beheading Egyptian Coptic Christians it had held hostage in Libya for weeks.
The video shocked many in Egypt, and spurred calls for the government to take action. In a late-night televised address Sunday, President Abdel Fattah el-Sisi promised that Egypt would respond.
"These cowardly actions will not undermine our determination," said Sisi, who also banned all travel to Libya by Egyptian citizens. "Egypt and the whole world are in a fierce battle with extremist groups carrying extremist ideology and sharing the same goals."
A spokesman for Egypt's military announced the airstrikes on state television Monday morning, the first time Egypt has acknowledged taking foreign military action since it fought in the Persian Gulf War in 1991.
"Let those far and near know that Egyptians have a shield that protects them," read the statement.
Several Libyan news sites posted photos of the aftermath of the strikes. BuzzFeed News could not independently verify the photos.
Sheera Frenkel is a cybersecurity correspondent for BuzzFeed News based in San Francisco. She has reported from Israel, Egypt, Jordan and across the Middle East. Her secure PGP fingerprint is 4A53 A35C 06BE 5339 E9B6 D54E 73A6 0F6A E252 A50F
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