Government forces loyal to Syrian President Bashar Assad used nonlethal chemical weapons just weeks ago, an unnamed Israeli security source has told the Israeli media.

The Jerusalem Post reported that the source confirmed claims made by the Syrian opposition last month that a chemical substance had been used on rebels in Harasta, a suburb of Damascus.

The chemical agent was used to incapacitate the rebel fighters, not kill them, the Times of Israel reported, also quoting an unnamed senior Israeli defense official.

The substance “neutralizes but does not kill,” the source was quoted as saying.

A Sunday, April 6, 2014 photo provided by the anti-government activist group Aleppo Media Center (AMC), which has been authenticated based on its contents and other AP reporting, shows civil defense rescue workers carrying the body of a victim of a Syrian government airstrike, in Aleppo, Syria. This photo is not connected with the new claims about chemical weapons use. AP Photo/Aleppo Media Center, AMC)

A Sunday, April 6, 2014 photo provided by the anti-government activist group Aleppo Media Center (AMC), which has been authenticated based on its contents and other AP reporting, shows civil defense rescue workers carrying the body of a victim of a Syrian government airstrike, in Aleppo, Syria. This photo is not connected with the new claims about chemical weapons use. (AP/Aleppo Media Center, AMC)

The incident the Israeli official confirmed occurred on March 27, and the health effects of the offending agent reportedly lasted for several hours.

The official further noted that the specific chemical used was not among those Assad’s government committed to dispose of under a September agreement.

Syrian opposition sources reported a second case of suspected chemical weapons use, which the Israeli official was unable to confirm. That alleged attack occurred within days of the first attack, also in the Damascus area.

The Jerusalem Post reported: “The Syria Deeply website cited the Syrian American Medical Society (SAMS), a group of Syrian-American doctors and surgeons traveling in and out of Syria, as condemning what it described as a ‘poisonous gas attack’ in Harasta.”

“Symptoms suffered by patients included hallucination, accelerated pulse, trouble breathing and, in some cases, suffocation,” SAMS reported.

At a Monday press conference, Israeli Defense Minister Moshe Ya’alon said 60 percent of Syria’s chemical weapons had been removed from the country.

He further said that Israel is keeping a close eye on the removal of the unconventional weapons, concerned they could otherwise land in the hands of the Shiite militant group Hezbollah.

Haaretz quoted Ya’alon as saying that Syria had destroyed its production line for manufacturing chemical weapons as well as most of the ammunition used to deliver the chemical weapons.

“In recent weeks the process of removing the material from Syria has quickened, after a short break, via a Danish or Norwegian ship in Latakia [Syria] and from there to an American site where the material will be destroyed,” Ya’alon said.

Under an agreement with the West, Assad committed to destroying his store of chemical weapons after a reported sarin gas attack last summer killed hundreds. That incident prompted the Obama administration to threaten a military attack on Syria.

The Syrian government failed to meet a Feb. 5 deadline to move all of its declared chemical agents out of the country, but has committed to a new timetable set for the end of this month.