The Lebanese Army said Israeli warplanes violated Lebanon's airspace yesterday, one day after rockets fired from south Lebanon sparked tit-for-tat clashes in which two militants were killed. "Ten enemy fighter-bombers violated Lebanese airspace twice in the middle of the day," the army said. The warplanes overflew the entire country and broke the sound barrier over the southern port city of Tyre.Israel said it wanted to avoid an escalation of fighting with militants in Lebanon after the worst flare-up of violence this year on the volatile border, but insisted the country would defend itself against attack. "Israel has no interest in an escalation on the northern border, but will know how to hurt those who try to hurt its citizens even more," Defense Minister Amir Peretz told Israeli radio earlier.