BEIRUT — An apparent Israeli missile attack on a Syrian military installation near Damascus International Airport shook the capital early on Thursday morning and raised tensions between the two hostile neighbors.
After nightfall, the Israeli military deployed its Patriot missile defense system to intercept a projectile incoming from Syria above the Golan Heights. The military did not elaborate on what it described as a "target" on Thursday night but Israeli media said a drone that had infiltrated from Syria was knocked out.
The target of the pre-dawn explosions near Damascus was not immediately known, but the blast could be felt at least 15 kilometers (9 miles) away. The Syrian military said the attack was carried out by Israel and aimed to "raise the morale of terrorist groups" the government maintains are waging war against President Bashar Assad's forces.
The Syrian military said it would continue its "war on terror" — government parlance for the battle against all groups trying to oust Assad.
Lately, Israel has appeared to be striking at military convoys and installations in Syria at a quickening pace, maintaining it has the right to prevent authorities in Damascus from transferring weapons across the border to the Lebanese militant Hezbollah group.
Hezbollah is a staunch ally of the Syrian government, which is mired in a six-year-long civil war, and also an avowed enemy of Israel, which occupied Lebanon for nearly two decades.
Israeli Minister of Intelligence Yisrael Katz would not comment directly on the incident but said any similar strike would be in line with established policy to interrupt weapons transfers.
"It absolutely matches our declared policy, a policy that we also implement," Katz told Israel's Army Radio.
Israel is widely believed to have carried out several airstrikes in recent years on advanced weapons systems in Syria — including Russian-made anti-aircraft missiles and Iranian-made missiles — as well as Hezbollah positions. It rarely comments on such operations.
Activists running the widely followed Damascus-focused Facebook page Diaries of a Mortar reported hearing several explosions before dawn, which they said could be felt across the Syrian capital.
Syria's state-run SANA news agency said Israel had fired several missiles from inside the Occupied Golan Heights, 60 kilometers (37 miles) south of Damascus, striking a military installation southwest of the airport that serves both military and civilian flights. It reported several explosions and material damage but no casualties. It was not clear how Israel was identified as the culprit.
"The buildings shook from the force of the blast," said a media activist who goes by Salam al-Ghoutawi, of the Ghouta Media Center, in the city's opposition-held northeastern suburbs, about 15 kilometers (9 miles) from the airport. He said he heard the roar of jets in the distance at the time.
A string of explosions could be seen silhouetted against the night sky in a video published by the center. Debris is seen flying out as the light of the explosions illuminated a sizeable blast cloud that took shape nearby. A pro-government site Damascus Now said the explosion was near the city's Seventh Bridge, which leads to the airport road.
Hezbollah's al-Manar media station reported an explosion at the fuel tanks and a warehouse next to the airport, which is 25 kilometers (16 miles) east of the city center. Al-Manar also speculated the blast was caused by an Israeli strike.
Hezbollah has sent thousands of its militants to fight alongside government forces in Syria's six-year-long civil war.
Syria's conflict, which pits Assad and his regional allies against local and foreign opposition forces inside his country, has left more than 400,000 people dead since it erupted in March 2011. The civil war is further complicated by militant factions such as al-Qaida's affiliate in Syria and the even more powerful Islamic State group, which in 2014 carved out a sizeable chunk of territory but has lately been losing ground in the face of a campaign by the U.S.-led international coalition.
No further details were immediately known about the missile fired by Israel's Patriot system on Thursday evening.
Last July, the air defense system shot at a drone that the Israeli military said had crossed into its airspace from Syria. The military said that drone returned to Syria. In 2014, Israel brought down a Syrian drone and fighter jet that had entered its airspace on two separate occasions.
In other developments earlier on Thursday, at least 19 people were killed in a string of air raids across the northwestern rebel-held Idlib province. Some of the raids appeared to target ambulances and medical centers.
The Civil Defense, a search-and-rescue organization, said four medical staff were killed in an attack on a university hospital in the town of Deir Sharqi, and four paramedics or ambulance operators died in an airstrike on an ambulance services charity in another town, Maarzita.
The activist-run Idlib Media Center said another four people were killed by barrel bombs dropped on the town of Khan Sheikhoun.
Also, the Britain-based Syrian Observatory for Human Rights said 19 civilians, including nine children, were killed around the northern province. The Civil Defense reported the same overall death toll.
The activists believe Russia or the Syrian government launched the raids. U.S. jets are also known to strike at positions in Idlib province, where they target al-Qaida-linked fighters.
Hundreds of thousands of Syrians displaced by the war have sought refuge in the rural province, now largely under the control of hard-line rebel groups. It borders Turkey to the north.
Meanwhile, the Syrian government on Thursday condemned French Foreign Minister Jean-Marc Ayrault for a statement he made the previous day saying Assad's forces were behind a sarin gas attack that killed nearly 90 people in Khan Sheikhoun earlier this month.
Ayrault had said samples from the site of the attack bore the traces of the chemical weapons believed to remain in Assad's arsenal.
The Syrian government said Ayrault's "lies and fabricated allegations" implicate France in "masterminding" the attack.
Associated Press writers Sara El Deeb and Hashem Osseiran in Beirut, Ian Deitch in Jerusalem, and Albert Aji in Damascus, Syria, contributed to this report.