Human Rights Watch condemned Hizbullah on Thursday for using cluster bombs on an estimated 113 occasions during this summer's war, according to research performed by the NGO's investigators.
Thursday's announcement also repeats earlier criticisms of Israel's firing of what the UN has estimated to be four million cluster bombs and submunitions.
"We are disturbed to discover that not only Israel but also Hizbullah used cluster munitions in their recent conflict, at a time when many countries are turning away from this kind of weapon precisely because of its impact on civilians," said Steve Goose, director of Human Rights Watch's Arms Division.
HRW spoke to people in the Israeli Druse village of Mughar whose family members - civilians - were wounded by Hizbullah's cluster bombing, as well as with Israel Police officials.
The NGO argued that the use of cluster bombs violated international law by not adequately distinguishing between combatants and civilians.
"Use of cluster bombs is never justified in civilian-populated areas because they are inaccurate and unreliable," Goose asserted.
Gerald Steinberg of NGO Watch questioned why it had taken Human Rights Watch three months to discover Hizbullah's tactic when it reported on Israel's use of cluster bombs much earlier.
"By putting out this report at such as late date basically you are saying they don't think it's very important," said Steinberg. "This report on Hizbullah's use of cluster weapons is far too little, far too late to undo the damage they did by one-sided condemnations of Israel over the last three months."
He said that HRW's only comprehensive report on the war had focused on alleged Israeli violations, as had the vast majority of its approximately 30 press releases on the conflict.