Reuters TV

A still image taken from Israeli Defence Forces (IDF) video footage shows what they say is a small unidentified aircraft shot down in a mid-air interception after it crossed into southern Israel on Oct. 6, 2012.

The leader of the Lebanese militant Hezbollah group has claimed responsibility for launching the drone aircraft that entered Israeli airspace earlier this week.

The rare admission Thursday by Hassan Nasrallah raises regional tensions at a sensitive time when the group's backers, Syria and Iran, are under pressure.

Israel shoots down unidentified drone

Earlier Thursday, Israeli Prime Minister Benjamin Netanyahu accused Hezbollah of launching the drone.

The unmanned aircraft was shot down by Israel, but the infiltration marked a rare breach of Israel's airspace. Hezbollah had been the leading suspect because of its arsenal of sophisticated Iranian weapons and a history of trying to deploy similar aircraft.

Nasrallah said in a televised speech that the drone was Iranian-made and went down near the Dimona nuclear reactor in the Negev Desert, after flying some 25 miles into Israel.

"The drone flew over sensitive installations inside southern Palestine," he said in a televised speech.

Hezbollah does not recognize Israel.

"Today we are uncovering a small part of our capabilities, and we shall keep many more hidden," Nasrallah added. "It is our natural right to send other reconnaissance flights inside occupied Palestine ... This is not the first time and will not be the last. We can reach any place we want" inside Israel, he said.

With a formidable arsenal that rivals that of the Lebanese army, Hezbollah is already under pressure in Lebanon from rivals who accuse it of putting Lebanon at risk of getting sucked into regional turmoil. Confirmation that Hezbollah was behind the drone could produce further internal strain as it pursues its longstanding conflict with Israel.

Israel routinely sends F-16s over Lebanon, breaking the sound barrier over Beirut and other places as a show of strength.

Hezbollah, a powerful Shiite group committed to Israel's destruction, has long served as an Iranian proxy along Israel's northern border. The two sides fought a brutal monthlong war in mid-2006. Hundreds of people were killed, and Hezbollah fired several thousand rockets and missiles into Israel before the conflict ended in a stalemate.

Hezbollah has attempted to send unmanned aircraft into Israel on several occasions, dating back to 2004. Nasrallah has claimed that the group's pilotless aircraft were capable of carrying explosives and striking deep into Israel.

The last known attempt by Hezbollah to use a drone took place during the 2006 war, when Israel shot down an Iranian-made pilotless aircraft that entered its airspace.

Since the fighting ended, the sides have been locked in a covert battle against one another.

Touring southern Israel on Thursday, Israeli Prime Minister Benjamin Netanyahu praised efforts to prevent land infiltrations from Egypt. He mentioned that Israel has been equally successful "in the air, just like we thwarted the Hezbollah attempt last weekend," his first public statement blaming Hezbollah.

Israel says the drone was not carrying explosives and appeared to be on a reconnaissance mission.

During the televised speech, Nasrallah denied sending fighters into Syria to help Hezbollah's ally President Bashar Assad to quell the rebellion in Syria.

"We did not fight alongside the regime until now. The regime did not ask us to do so and also who says that doing so is in Lebanon's interest?" Nasrallah said.

Hezbollah's opponents have accused it of sending fighters into Syria. Last month, the U.S. Treasury sanctioned Nasrallah for helping Assad crush anti-government protests, as well as two other members for the group's "terrorist activities" in general.

The Associated Press and Reuters contributed to this report.

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TRIPOLI, Lebanon – It only takes a two-minute stroll down Syria Street to see why so many people are so worried about what might happen next in Lebanon.

A hole punched through the wall of the mosque by a rocket or mortar shell, smoke-blackened masonry, shops and apartments bearing the pockmarks of fierce gun battles.

Syria Street is the aptly named thoroughfare that separates rival factions in Lebanon’s second city.

For much of the past week, the two sides have been waging a mini-civil war.

It is a direct spill over from the chaos in neighboring Syria.

Photos: Violence on the streets of Tripoli

One side of the street is home to a hard-line Sunni Muslim militia who run guns to rebels across the border.

“President Assad is trying to destroy us,” says Sheik Bilal Masri, by way of explanation. “They cause trouble here to take the pressure of them in Damascus.”

We meet a small group of his men. They are well-armed and apparently spoiling for a fight.

Not many yards away, posters of Syria’s President Bashar Assad striking stern military poses adorn walls on the other side of the street.

Here the people share Assad’s Alawite faith and, it seems, the same determination to defend his regime.

Omar Ibrahim / Reuters

A man hides behind sandbags amid clashes in the Bab al-Tebbaneh neighborhood in Tripoli, Lebanon, on Thursday.

“No one wants a civil war in Lebanon,” a local Alawite leader tells me.  “But everyone should be warned: There will be repercussion for anyone who tries to meddle in Syria.”

Conflict along Syria Street is nothing new. But the outside world began to take notice on Monday when for the first time in four years, gun battles broke out on the streets of Lebanon’s capital, Beirut.

2 killed, 18 hurt as Syria conflict spills over into Lebanon

It was a brief glimpse back into the abyss for a nation scarred by years of civil strife.

In 2005, Syrian troops were forced to withdrawal from Lebanon, but Damascus is still a big player in the fractured politics of a country that sees rival Muslim and Christian sects share power in a set of uneasy alliances.

Syria’s most powerful friend here is Hezbollah, the militant Shiite group that probably holds the key to whether Lebanon survives in one piece.

Inside Syria rebel stronghold: 'The city is on mute' 

Its heartland in the south of Beirut has been tense, but so far its leader, Hassan Nasrallah, has kept his forces out of the fray.

But for how long?

The fatal shooting of two Sunni clerics followed by the kidnapping of Lebanese Shiite pilgrims in Syria shows how unpredictable events have become.

A message to Assad? War games held near border

For more than two decades, Timur Goksel has watched events in Lebanon. Once of the U.N. Mission here, he now lectures at the American University in Beirut.

He tells me the country has rarely felt so dangerous.

“I hope I am wrong because this is scary. If the faction leaders lose control of these young guys with the guns then we’re in trouble,” he said.

Their bloody history has taught the Lebanese to be a fatalistic people.

“The country is at boiling point,” another seasoned observer told me with a shrug.  “What is coming will be very bad.”

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