Syria’s chief of staff on Thursday told troops that the war with Israel is ongoing and will never end, Syrian state media reported.

General Ali Abdullah Ayoub’s statements to Syrian Army soldiers came a day after a reported Israeli airstrike targeted a military installation outside Damascus, killing two and injuring five, according to state media.

Ayoub also charged that Israel was backing rebel groups who were conducting “organized terrorism against the Syrian people.”

The two countries are formally in a state of war, but a tenuous ceasefire has held since 1974 despite multiple cross-border incidents in recent months. Opposition groups have fought a 22-month civil war against Syrian President Bashar Assad. The conflict has left over 60,000 Syrians dead and displaced millions, according to the United Nations.

Israeli warplanes conducted a rare airstrike inside Syria overnight Tuesday, according to US officials who said the target was a convoy believed to be carrying anti-aircraft weapons bound for Hezbollah, the powerful Lebanese terrorist organization allied with Syria and Iran. The trucks were next to the military research facility identified by the Syrians, and the strike hit both the trucks and the facility, said one official, who spoke on condition of anonymity because he was not authorized to speak about the operation.

The Syrian military has denied the existence of any weapons shipment and said a military research facility outside Damascus was hit.

Syrian sources told the London-based Arabic daily al-Quds al-Arabi on Friday that the objective of the reported Israeli airstrike was to test Damascus’s preparedness and air defense abilities, rather than deal with significant damage to its military infrastructure. They further claimed that the labs in the facility were not destroyed in the attack.

On Thursday, Syria threatened to retaliate, while Hezbollah condemned the attack as “barbaric aggression.” Iran, which supplies arms to Syria, Hezbollah and the Hamas militant group in Gaza, said the airstrike would have significant implications for Israel. Syrian ally Russia said it appeared to be an unprovoked attack on a sovereign nation.

Syria’s ambassador to Lebanon, Ali Abdul-Karim Ali, said Damascus “has the option and the capacity to surprise in retaliation.” He told Hezbollah’s al-Ahd news website that it was up to the relevant authorities to choose the time and place.