Emir Nader,Jerusalemand Toby Mann
Israel's military says it has begun a wave of strikes across Lebanon following an announcement by Prime Minister Benjamin Netanyahu that his country will intensify its attacks on Hezbollah.
The Israel Defense Forces (IDF) said it had launched strikes against Hezbollah in the eastern Bekaa Valley and other parts of the country.
Hezbollah, a Shia Muslim armed group in Lebanon backed by Iran, said it had retaliated by carrying out 22 drone and rocket attacks and that its targets included Israeli soldiers, tanks, barracks and buildings.
Earlier this month, Lebanon and Israel agreed to extend a 45-day ceasefire which began in mid-April, though attacks between Israel and Hezbollah have continued.
On Tuesday morning, the IDF said it had "struck more than 100 Hezbollah infrastructure sites and terrorists".
Twelve people are said to have been killed in an attack on the village of Mashghara in the Bekaa Valley, Lebanese local media reported.
The IDF said several strikes were conducted "within seconds against Hezbollah infrastructure sites [in Mashghara] where terrorists [sic] activity was identified". It added "the terrorists were eliminated" during the attack.
The Israeli military has issued an evacuation order for the southern town of Nabatieh due to possible strikes.
Hours earlier, in a video statement, Netanyahu said Israel was "at war with Hezbollah" and the military has been told to "deal them a crushing blow".
Netanyahu said Israel's military offensive against Hezbollah had "eliminated... over 600 terrorists in the last few weeks".
He continued: "But what this requires of us now is to increase the strikes, to increase the intensity."
Two far-right Israeli ministers, Bezalel Smotrich and Itamar Ben Gvir, have called for an expansion of the military campaign, including into Beirut.
Hezbollah said it had used drones and rockets to attack sites across southern Lebanon and northern Israel on Monday, in response to what it called Israel's "violation of the ceasefire".
The Israeli authorities are particularly concerned about the use of new fibre optic drones by Hezbollah, which has been using them to strike Israeli troops now occupying a strip of land in the south of the country, as well as Israeli villages on the other side of the border.
Officials from Lebanon and Israel, which do not have formal diplomatic relations, are due to hold further negotiations in Washington next week.
Lebanese President Joseph Aoun has demanded a complete Israeli withdrawal from southern Lebanon.
Since the ceasefire agreement was signed on 16 April, Israeli attacks have been largely confined to the south of the country, where Israeli troops remain and from where Israel says drones and rockets have been launched.
The expansion of Israel's campaign came as the Iranian government insisted that an emerging peace deal with the US should include a complete ceasefire on all fronts in the regional war.
Israel's government has been opposed to ending the fighting against Hezbollah.
Ten Israeli soldiers have been killed since the initial ceasefire with Lebanon was agreed. More than 400 people in Lebanon have been killed by heavy Israeli bombardment in the same period, including many paramedics and emergency service workers.
Israel has issued near daily orders for Lebanese citizens to leave their homes in new areas in the south of the country, adding to the more than one million people displaced.
Lebanon was drawn into the current round of fighting after the US and Israel launched a war against Iran on 28 February. Hezbollah, an ally of Iran, fired rockets into Israel in retaliation for an Israeli strike that killed the Iranian supreme leader Ayatollah Ali Khamenei.
Israel responded with an air campaign across Lebanon and a ground invasion, with more than 3,000 people killed in Israeli attacks according to the Lebanese Ministry of Health.
Lebanon's government has been pursuing attempts to disarm Hezbollah but maintains a ceasefire is necessary in order to complete what it says is a complex task.