The Islamic State group on Friday was removed from the last two major towns it held along the Iraq-Syria border following raids by forces on either side of the border near the Euphrates Valley.
The jihadist group's self-proclaimed caliphate was in tatters after it lost its urban strongholds in Syria and Iraq, with the simultaneous assaults on Deir el-Zour in Syria and Al-Qaim in Iraq leaving IS in control of little more than small plots of territory scattered along the border.
The Syrian army announced that, regarding Deir el-Zour, IS lost "the headquarters of the organization's leadership" and, in effect, "their capacity to direct terrorist operations."
"The army forces ... restored security and stability to all of Deir el-Zour city," a spokesman for the Syrian army command said in a statement broadcast live on state television. "Deir el-Zour represents the final phase in the complete elimination of [IS]."
Syrian forces began their assault on Deir el-Zour in September after the city had been under IS control for nearly three years. Engineering units from the Syrian army are now searching for any mines or other explosives left behind by the fleeing jihadists.
On the Iraq side of the border, troops captured Al-Qaim within hours of taking control of a nearby border crossing. Iraqi Prime Minister Haider al-Abadi praised the troops for their efforts to secure Al-Qaim in what he called "record time."
The operation to retake Al-Qaim began several days ago. The U.S.-led coalition fighting in Iraq has dubbed the offensive "the last big fight," as Iraqi forces have already recaptured more than 90 percent of the territory previously seized by IS in 2014.
The U.S. military congratulated Iraqi forces on the victory.
"Iraqi Security Forces have fought hard to reach this point, and their battle-proven troops captured ISIS's last Iraqi stronghold swiftly and thoroughly," said Maj. Gen. Robert P. White, Commanding General of the Combined Joint Forces Land Component Command - Operation Inherent Resolve.
There are about 1,500 IS fighters remaining in the area surrounding Al-Qaim, according to the U.S. military.