Israel said Tuesday there is no proof supporting Syrian claims that chemical weapons were used against rebels fighting to bring down President Bashar al-Assad. 

Activist accounts gathered by the Syrian Observatory for Human Rights - a group with a network of activists across the country - stated that a poison gas attack occurred in the city of Homs on Sunday, Dec. 23, according to Reuters. Six rebel fighters allegedly died after inhaling gas released by government forces in rebel-held districts of the city.  

Mousab Azzawi, chairman of the London-based Syrian Observatory and a doctor, told NBC News that his organization received reports from three eyewitnesses on Sunday about the poisoning. He also expressed his concern that the attack might be a sign that Assad's government might use chemical weapons as means for an attack against any opposition. However, Israeli officials see differently. 

"We have seen reports from the opposition. It is not the first time. The opposition has an interest in drawing in international military intervention," Vice Prime Minister Moshe Yaalon said on Army Radio. "As things stand now, we do not have any confirmation or proof that (chemical weapons) have already been used, but we are definitely following events with concern."

When asked about images that reportedly showed patients being treated for possible gas poisoning from the attack, Yaalon said, "I'm not sure that what we're seeing in the photos is the result of the use of chemical weapons. It could be other things."

Senior Israeli defence official Amos Gilad said on Sunday that Syria's chemical weapons were "still secure" even though rebels control parts of the country now.

The activist accounts are difficult to verify because the country's government restricts media access in Syria and an investigation into the matter continues.

Israel is concerned about the reports claiming chemical weapons were used especially because, as Syria's southern neighbor, if the weapons were to fall into the hands of Islamist militants or Hezbollah fighters, it could be detrimental to the safety of Israel's citizens.

Tags: syria israel