The Israel Defense Forces launched strikes on what it described as three Hezbollah command centers in southern Lebanon, saying the attacks were a response to ceasefire violations.

“These strikes came in response to the terror organization Hezbollah’s continued targeting of our forces operating in the security zone,” Avichay Adraee, an IDF spokesperson, said on social media.

The fighting in southern Lebanon between Israel and Hezbollah, a militant group backed by Iran and based in Lebanon, has threatened to throw off track ongoing negotiations between Washington and Tehran.

The U.S. on Friday announced a “framework” for future talks between Israel and Lebanon, which would be facilitated by Washington, seeking to end the fighting in Lebanon. Hezbollah on Saturday responded to that framework, saying in a statement it was rejecting the agreement, continuing its resistance and holding on to its weapons.

Israeli officials, including Prime Minister Benjamin Netanyahu, have said Israel plans to remain in a “security zone” in southern Lebanon.

The Israeli Air Force struck overnight alleged Hezbollah command centers in Nabatieh and Mayfadoun in southern Lebanon, the IDF said early Monday.

“Additionally, troops struck and dismantled a launcher that Hezbollah continued using to attack them,” the IDF said on social media.