BEIRUT — Syrian government forces on Sunday briefly captured four villages east of the Euphrates River in the eastern province of Deir el-Zour after rare clashes with U.S.-backed Kurdish-led fighters, then lost the area in a counteroffensive by the Kurdish-led force.
The area close to the border with Iraq has been the site of recent clashes between the two sides that had been focusing on fighting the Islamic State extremist group. The IS had declared its caliphate in parts of Syria and Iraq.
Crossings into the east bank of the Euphrates in eastern Syria by government forces have been rare.
Hours later, Syrian state television reported airstrikes it described as a "new aggression," with missiles targeting a number of military outposts in northern Syria.
Syrian TV reported early Monday that the missiles targeted outposts in the Hama and Aleppo countryside. It did not say who fired the missiles or whether there were any casualties or damage. The news comes less than two weeks after a similar report of airstrikes on government military installations in the central Homs region and the suburbs of Damascus. But the military later said a false alarm had set off air defense systems.
The Britain-based Syrian Observatory for Human Rights, which monitors the war in Syria through activists on the ground, reported loud explosions in the Hama countryside and Aleppo province resulting from missiles targeting a base of the 47th Brigade in Hama that houses Syrian government and allied Iranian forces. It also reported missiles hitting positions near the Nairab air base and Aleppo airport. It said the source of the missiles was not immediately known, and had no information on casualties.
Earlier this month, seven Iranian military personnel were killed in an airstrike on Syria's T4 air base in the central Homs province. Syria, Iran and Russia blamed Israel for that attack. Israel, which has frequently targeted what it says are weapons shipments to the Lebanese militant group Hezbollah in Syria, did not confirm or deny it.
The U.S., Britain and France also carried out joint airstrikes on Syrian government facilities April 13, in retaliation for a suspected chemical weapons attack on a rebel-held town near Damascus they blamed on President Bashar Assad's government.
There was no immediate comment from Israel or the United States.
State news agency SANA said the villages briefly captured by government forces Sunday were held by the U.S.-backed Syrian Democratic Forces, adding that they are close to the provincial capital, also called Deir el-Zour. The SDF said in a statement later that it regained control of the whole area it earlier lost.
Much of Deir el-Zour province was held by the Islamic State group but over the past year Syrian government forces captured most areas west of the Euphrates while SDF fighters took areas east of the river.
On Feb. 7, pro-Syrian government fighters attacked SDF positions east of the river and faced a ferocious U.S. counterattack that left dozens, including Russians, dead.
SDF spokesman Kino Gabriel said in a statement earlier Sunday that the Syrian army attack coincided with "our forces' preparations to complete the Island Storm campaign" to liberate the remaining areas east of the river from IS. Gabriel said the Syrian army and pro-government fighters began targeting SDF fighters to impede "the launching of our campaign against terrorism. Our forces are responding in self-defense."
"We affirm that we are determined to eradicate terrorism from its roots and to assert our right to self-defense," Gabriel said about IS. "We consider this aggression by regime forces to be a support for terrorism and falls within the attempts to impede the war on terrorism."
The Britain-based Syrian Observatory for Human Rights, a war monitor, said Sunday's offensive left six SDF fighters dead and 22 wounded adding that there were also casualties on the government side.
Gabriel issued another statement later saying all the area lost earlier was regained by SDF fighters. He said Syrian troops were backed by Russian fighters adding that after the SDF's counteroffensive, government forces "are now far away."
The Observatory's chief Rami Abdurrahman said SDF fighters took back most of the area except for one village.
The fighting in eastern Syria came as Syrian state media and the Observatory reported that an agreement was reached between the Syrian government and several rebel factions to evacuate the last three rebel-held suburbs of the capital Damascus.
SANA said the deal will let opposition fighters who want to evacuate the area head to rebel-held regions while those who decide to stay can hand over their weapons and benefit from an amnesty.
The Observatory said rebels who will leave will head to the northwestern province of Idlib, the northern town of Jarablus, and the southern province of Daraa that borders Jordan.
The three suburbs of Babila, Beit Sahem and Yalda have been held by rebels for years and their capture would bring all suburbs of the capital under government control.
The agreement came as government forces captured more areas from the IS in the nearby Palestinian refugee camp of Yarmouk and the neighborhood of Hajar al-Aswad.
SANA said troops captured most of the Qadam neighborhood as well as the Assali and Joura quarters in Hajar Aswad.