Islamic State (IS) has reportedly seized the last Syrian government-controlled border crossing between Syria and Iraq, the Al Tanf crossing in Homs, as government troops retreated from the region, said the Syrian Observatory for Human Rights (SOHR).
The monitoring group added that the terror group was now in control of "more than 95,000 sq km of Syria, which is 50 percent of the country's entire territory," reported the BBC.
The United States has said that battling the militants would be a "difficult challenge."
The latest advance came after IS took over the ancient Syrian city of Palmyra and the Iraqi city of Ramadi recently.