Here's the Human Rights watch report on the four million dropped in spite by them in 2006:

"The Israel Defense Forces (IDF) issued a short statement on December 24, 2007, on the results of an internal inquiry into its controversial use of cluster munitions during the 34-day war with Hezbollah in July and August 2006.[1]During that short conflict, the IDF rained an estimated 4 million submunitions on south Lebanon, the vast majority over the final three days when Israel knew a settlement was imminent... "

https://www.hrw.org/report/2008/02/16/flooding-south-lebanon/israels-use-cluster-munitions-lebanon-july-and-august-2006

Here's the UN report:

https://www.unocha.org/publications/report/lebanon/lebanon-cluster-bomb-fact-sheet

They had used them before and notably Ronnie Regan banned their export to Israel as far back as 1984:

https://www.washingtonpost.com/archive/politics/1982/07/20/president-halts-shipment-of-cluster-shells-to-israel/aeba41dc-ba63-4b2b-8b6f-91f33f6649f9/