Syrian state TV blamed the strike that targeted pro-regime forces and caused multiple casualties on the US-led coalition combating the terrorist group, but a spokesman for the coalition said there were no coalition strikes in the area near Abu Kamal.
The Israel Defense Forces declined to comment on the strike, per its normal policy.
US officials have said that many pro-regime militias that are also aligned with Iran operate in the border area between Syria and Iraq.
Israel has repeatedly warned that it would target Iranian-linked groups in Syria.
"We will take action - and are already taking action - against efforts to establish a militarily presence by Iran and its proxies in Syria both close to the border and deep inside Syria. We will act against these efforts anywhere in Syria," Israeli Prime Minister Benjamin Netanyahu said Sunday at a cabinet meeting.
Netanyahu spoke with US Secretary of State Mike Pompeo and Russian President Vladimir Putin over the weekend, two of the key players in influencing Israel's policy and actions over Syria.
Sunday's strike was very different from those normally attributed to Israel. Generally, strikes by Israel occur in the western region of Syria, principally in the area around Damascus and Homs. Recently, these strikes have targeted Iran's infrastructure and military presence in Syria, which Israel has staunchly opposed. Israel also has struck shipments of advanced weapons from Syria to Hezbollah in Lebanon in the past.
This attack in Eastern Syria is hundreds of miles away from that area, and the target -- pro-regime forces -- differs from what would be Israel's usual mark, namely Iranian military positions.