BEIRUT (AP) — Twelve Israeli warplanes violated Lebanese airspace in less than 24 hours, flying low in several sorties over villages in southern Lebanon, the Lebanese military said Wednesday.

A Lebanese security official said there has been increased Israeli activity over Lebanese airspace in the past week.

The flights come amid Israeli concerns about the civil war in neighboring Syria and fears that weapons could reach hostile groups in Syria or the militant anti-Israel Hezbollah group in Lebanon.

Earlier this week, Israel moved a battery of its new "Iron Dome" rocket defense system to the northern city of Haifa, which was battered by Hezbollah rocket fire in the 2006 Israel-Hezbollah war. The Israeli army called that move "routine."

A Lebanese army statement said the last of the sorties took place at 2 a.m. local time Wednesday. It said four warplanes which flew in over the southernmost coastal town of Naqoura hovered for several hours over villages in south Lebanon before leaving Lebanese airspace.

It said similar flights by eight other warplanes were conducted Tuesday.

There was no immediate comment from Israel. The Lebanese official said the flights were part of "increased activity" in the past week but did not elaborate. The area of Lebanon where the flights took place borders southern Syria.

Israeli violations of Lebanese airspace are not uncommon and Lebanese authorities routinely lodge complaints at the U.N. against the flights.