BY DIAA HADID
JERUSALEM (AP) -- Israel shot down a drone Thursday as it approached its northern coast from neighboring Lebanon, raising suspicions that the Hezbollah militant group was behind the infiltration attempt.
Hezbollah denied involvement, but the incident was likely to heighten Israeli concerns that the Shiite militant group is trying to take advantage of the unrest in neighboring Syria to strengthen its capabilities.
Prime Minister Benjamin Netanyahu, who was in a helicopter in northern Israel at the time of the incident, said he viewed it with "utmost gravity."
Israeli military spokesman Lt. Col. Peter Lerner said the unmanned aircraft was detected as it was flying over Lebanon and tracked as it approached Israeli airspace.
He said the military waited for the aircraft to enter Israeli airspace, confirmed it was "enemy," and then an F-16 warplane shot it down, smashing its wreckage into the sea about five miles (eight kilometers) off the northern port of Haifa. Lerner said Israeli naval forces were searching for the remains of the aircraft.
He said it still was not clear who sent the drone, noting it flew over Lebanese airspace, but that it could have originated from somewhere else.
Other military officials, speaking on condition of anonymity because they were not permitted to talk to the media, said they believed it was an Iranian-manufactured aircraft sent by Hezbollah. The Lebanese group sent a drone into Israeli airspace last October that Israel also shot down.
Officials said Netanyahu was informed of the unfolding incident as he was flying north for a cultural event with members of the country's Druse minority. They said his helicopter briefly landed while the drone was intercepted then continued on its way.
"On my way here in the helicopter, I was told that there is an infiltration attempt of a drone inside the skies of Israel," Netanyahu said in the northern Arab-Israeli town of Daliyat al-Karmel. "We will continue to do everything necessary to safeguard the security of Israel's citizens."
Despite the denial, the incident was likely to raise already heightened tensions between Israel and Hezbollah, a bitter enemy that battled Israel to a stalemate during a monthlong war in 2006.
A senior Lebanese security official, who spoke on condition of anonymity in line with regulations, said Lebanon had no information on Thursday's incident.
When Israeli military shot down a Hezbollah drone on Oct. 6, it took days for Hezbollah leader Sheik Hassan Nasrallah to confirm it. He warned in a speech that it wouldn't be the last operation by the group. He said the sophisticated aircraft was made in Iran and assembled by Hezbollah.
Netanyahu repeatedly has warned that Hezbollah might try to take advantage of the instability in neighboring Syria, a key Hezbollah ally, to obtain what he calls game-changing weapons.
Israel has all but confirmed that it carried out an airstrike in Syria earlier this year that destroyed a shipment of sophisticated anti-aircraft missiles bound for Hezbollah.
Israel's military has also stepped up its air surveillance over Lebanon. On Thursday morning, Israeli warplanes flew over the Christian town of Jezzine and the highlands of the Iqlim al-Tuffah province, a Hezbollah stronghold in southern Lebanon, the country's state-run National News Agency reported.
The Lebanese army also reported Israeli jets violated Lebanese airspace on Tuesday and Wednesday.
Some analysts said Hezbollah might be trying to divert attention from its involvement in the increasingly sectarian Syrian civil war. The Shiite militants have openly sided with the regime of Bashar Assad in its battle against mostly Sunni rebels.
Jonathan Spyer, senior research fellow at the Herzliya Interdisciplinary Center near Tel Aviv, said Hezbollah was facing discontent among its Shiite base in Lebanon, and more broadly among other Arabs for its participation in the Syrian conflict.
He said the group was likely trying to show that its real enemy was the Jewish state, in an effort to shore up support.
Spyer said sending a drone appeared to be a "fairly calibrated provocation," intended to be low key enough not to provoke an Israeli military response in Lebanon.
"I wouldn't be surprised if we see more of these kinds of incidents in the weeks and months ahead," he said.
Associated Press writers Zeina Karam in Beirut and Josef Federman in Jerusalem contributed to this report.
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