BEIRUT  — Hundreds of people returned to eastern Aleppo neighborhoods Friday to check on their homes after the last opposition fighters left the city, picking through debris and wreckage for personal belongings blasted by years of fighting.

In a sign of the immense challenges that still lie ahead for President Bashar Assad, rebels outside the city shelled a neighborhood in Aleppo, killing three people in the first bombardment since government forces took full control of Syria’s largest city a day earlier, state TV reported.

The rebel surrender in Aleppo ended a brutal chapter in Syria’s nearly six-year civil war and marked Mr. Assad’s most significant victory since an uprising against his family’s four-decade rule began in 2011. But large parts of the war-ravaged country remain outside his control, including rural areas in Aleppo province south and west of the city where opposition fighters still operate.

Mr. Assad has said that the most important priority after securing Aleppo will be fortifying the countryside around it before moving on to other strongholds outside his control, including the nearby province of Idlib, west of Aleppo, and the city of Raqqa controlled by the Islamic State group in eastern Syria.

Syrian TV said rockets that hit the neighborhood of Hamadaniyeh Friday were fired by insurgents based southwest of Aleppo.

Associated Press footage from inside neighborhoods in eastern Aleppo taken over by the army after the last rebels were bused out a day earlier captured the staggering destruction: Row after row of destroyed buildings, many with blown out doors and windows, and toppled floors, along debris-strewn streets lined with charred vehicles. Not a single building appeared intact.

In the Sukkari, Ansari and Amiriyeh neighborhoods, army experts were dismantling explosives and booby-traps left behind by rebels.

Hundreds of people walked through the Bustan al-Qasr crossing, a passageway that separated rebel-controlled eastern Aleppo from the government-controlled al-Masharqa district, which was closed years ago, cutting off links between the two sides of the divided city.

The Syrian government’s recapture of Aleppo after a prolonged and punishing air assault leaves Mr. Assad in control of almost all major urban areas — and poised to play a role in the world community’s broader war against jihadis clinging to parts of Syria. It is a devastating a blow for the opposition, whose main backer, Turkey, is now heavily engaged with Moscow in searching for a settlement to the six-year war in Syria.

In Moscow, President Vladimir Putin, one of Mr. Assad’s key backers, said it’s necessary to establish a cease-fire across the entire territory of Syria, to be followed by peace talks. He said the leaders of Turkey and Iran, which have helped broker the withdrawal of the remaining civilians and militants from Aleppo, have agreed that Syria peace talks should be held in Kazakhstan’s capital, Astana, and Mr. Assad has agreed.

First Published: December 24, 2016, 3:42 a.m.