BEIRUT -- The Syrian government took full control of Aleppo on Thursday for the first time in four years after the last opposition fighters and civilians were bused out of war-ravaged eastern districts, sealing the end of the rebellion's most important stronghold.

The evacuations ended a brutal chapter in Syria's nearly six-year civil war, allowing President Bashar Assad to regain full authority over the country's largest city and former commercial powerhouse. It marked his most significant victory since an uprising against his family's four-decade rule began in 2011.

The announcement was made via an army statement broadcast on Syrian state TV shortly after the last four buses carrying fighters left through the Ramousseh crossing.

"Thanks to the blood of our heroic martyrs, the heroic deeds and sacrifices of our armed forces and the allied forces and the steadfastness of our people, the General Command of the Army and the Armed Forces announces the return of security and stability to Aleppo," an army general said in the statement.

Western Aleppo erupted in heavy celebratory gunfire, with Syrian TV showing uniformed soldiers and civilians shouting "Aleppo, Aleppo!" and "God, Syria and Bashar only!"

"No more east and west; Aleppo is back for all Aleppans," said the Syrian TV correspondent, surrounded by people waving Syrian flags.

For Syria's opposition, it was a crushing defeat that signaled the start of a new struggle to forge a way forward.

Ahmad al-Khatib, an opposition media activist who left the city before the siege, said the fall of Aleppo was a date "we'll never forget and we will never forgive."

"Let the world bear witness that Bashar Assad has killed and displaced and destroyed Aleppo, and he celebrates in his victory over the blood and offspring of Aleppo ... with the agreement of the Arab and Western nations," he posted on Twitter.

The ancient city had been divided into rebel and government parts since 2012, when rebels from the countryside swept in and took hold of eastern districts. That set the stage for more than four years of brutal fighting and government bombardment that laid waste to those neighborhoods.

The army statement said the victory in Aleppo is a "strategic transformation and a turning point in the war on terrorism and a deadly blow to the terrorist project and its supporters."

It was a further incentive to keep fighting to "eradicate terrorism and restore security and stability to every span of the homeland," it added.

Earlier in the day, Assad said his forces' achievements in Aleppo are a "major step on the road to wiping out terrorism" and ending the civil war.

The rebel evacuations were set in motion after a monthslong siege and Russian-backed military campaign.

Years of resistance were stamped out in a relentless campaign over the past month that saw hospitals bombed, bodies left unburied and civilians killed by shells as they fled for safety.