IDF fighter jets shot down an unmanned aircraft off the coast of Haifa Thursday. According to a military source, the aircraft took off from Lebanon and was apparently sent by Hezbollah.

Deputy Defense Minister Danny Danon accused the Iranians of using Hezbollah to test Israel.

“We’ll respond where we find fit, but there will be a response,” he said according to press reports.

The incident caused some drama in the skies over northern Israel, where Prime Minister Benjamin Netanyahu was flying to an event in a Bedouin village.

The prime minister’s helicopter was forced to make an emergency landing as jets scrambled to identify and intercept the aircraft at about 2 p.m.

“I view with utmost gravity this attempt to violate our border. We will continue to do everything necessary to safeguard the security of Israel’s citizens,” Netanyahu said after the incident, quickly resuming his schedule.

The IDF Spokesperson’s Unit said it could not confirm that the drone was sent by Hezbollah, which has flown drones over Israel in the past, including last October.

But 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.

Hezbollah denied any involvement, a news flash on the group’s Al-Manar TV station reported.

A senior Lebanese security official, who also spoke on condition of anonymity in line with regulations, said Lebanon had no information on Thursday’s incident.

Israeli navy and air force troops were sent to search the area where the aircraft was intercepted in order to prevent possible entry of additional drones and to locate debris which might shed light on the aircraft’s mission.

The plane was identified while still in Lebanon and IDF fighter jets were immediately scrambled to track it, the IDF said. Once it became clear that the drone was not an IDF or civilian aircraft, a decision was made to intercept the drone.

It was shot down by an F-16 fighter jet some five miles off the Haifa coast at 6,000 feet in the air, the IDF said.

A spokesperson from the UN peacekeeping force in southern Lebanon said UNIFIL had learned of the incident via the media and was investigating the report, Lebanon’s Daily Star newspaper reported..

This is the second known instance in which the Lebanese terrorist group has sent a drone into Israeli airspace in the last year. In October, the Israeli Air Force shot down an unmanned aircraft in a similar incident in southern Israel.

A military source told Walla news that Hezbollah has been making great efforts in recent years to obtain Iranian drones for spying and bombing sorties. “The IAF has trained for drone interceptions and has shown successes to date, despite the difficult nature of such missions,” the source added.

The incident came several days after the Knesset held a special discussion on dangers posed by a large ammonia tank in the city and other chemical plants, which could create a major disaster if attacked.

“It is now time to prepare in terms of protection and removal of the gas and petrochemical facilities in the Haifa Bay,” Haifa Mayor Yona Yahav said after receiving an update on the drone interception.

Earlier on Thursday, IAF jets were spotted flying over southern Lebanon near the border with Syria, the Lebanese national news agency reported.

According to the agency, fighter planes were seen over the town of Jezzine in the south, and in the Al-Touffah mountain region.

The report was not confirmed by the IDF.

During a visit to the Bedouin village of Kfar Joulias in northern Israel, Netanyahu said Israel was deeply concerned about the situation in Lebanon and Syria.

“Syria is falling apart and Lebanon is unstable. Both places present a considerable threat to Israel,” the prime minister said.

“In Syria there are two threats,” Netanyahu continued. “The first threat is leakage of advanced weapons to terrorist organizations, and the second is an attempt by terrorists to infiltrate our borders and shoot at our communities.”

Netanyahu has recently warned that Hezbollah might try to take advantage of the instability in neighboring Syria to obtain what he called game-changing weapons.

Stuart Winer, Mitch Ginsburg and Aaron Kalman contributed to this report from The Times of Israel. The Associated Press also contributed to this report.