The Israeli aircraft broke the sound barrier over UN peacekeepers' headquarters in the southern port of Naqura before buzzing the cities of Tyre and Sidon, police said.

That patrol by two fighter bombers was one of several during the morning that prompted anti-aircraft batteries of the Shiite Muslim militant group Hezbollah to burst into action, UN peacekeeping force spokesman Timur Goksel said.

Hezbollah said it had opened fire on three separate Israeli flights over the south.

The renewed overflights came despite a warning from the United Nations earlier this month that Israel risked sparking an escalation in an already tense Middle East.

"This worrying resumption ... of overflights deep into Lebanon serves only to heighten tension during this delicate period," said Staffan de Mistura, the personal representative in southern Lebanon of UN Secretary General Kofi Annan.

"The United Nations calls again for a halt to these violations of Lebanese airspace."

SPACE.WIRE