Trucks carrying food and medicine have entered a besieged Syrian town near the Lebanese border as part of a large-scale UN-supported aid operation in the country.
An Associated Press team saw three trucks enter Madaya, where a group of residents had gathered, hoping to receive desperately needed assistance.
The town, about 15 miles north-west of Damascus, has been blockaded for months by government troops and the Lebanese militant group Hezbollah. Opposition activists and aid groups have reported several deaths from starvation in recent weeks.
Simultaneously, trucks began entering the Shiite villages of Foua and Kfarya in northern Syria, both under siege by rebels seeking to oust President Bashar Assad.
The UN-supported aid operation was agreed on last week.
Red Cross spokesman Pawel Krzysiek wrote on his Twitter account that the first trucks entered Madaya, Foua and Kfarya, and said offloading of aid was expected to last throughout the night.
The situation in Madaya is the latest example of both sides using hunger as a weapon in Syria's war, now in its fifth year.
The town has attracted particular attention in recent days because of reports of deaths and images of severely malnourished residents that have circulated across social media. The images prompted a media war two weeks ahead of a new round of peace talks between the government and opposition expected to take place in Geneva.
Some government supporters have used social media to mock the photos, saying they were fake, while others claimed it was the rebels who were withholding food from needy residents.
The aid group Doctors Without Borders says 23 patients have died of starvation at a health centre it supports in Madaya since December 1 - including six infants under one-year-old and five adults over the age of 60.
Yacoub El Hillo, the UN's resident and humanitarian coordinator in Syria, said almost 42,000 people in Madaya are at risk of further hunger and starvation.
In Madaya, Hezbollah's Al-Manar television channel showed a group of people, including women and children, waiting for the convoys at the town's main entrance.
In interviews, they accused fighters inside of hoarding humanitarian assistance that entered the town in October and selling the supplies to residents at exorbitant prices.
"Our children are dying of hunger," a school teacher told the station, saying she walked to the entrance of the town to make sure she received the assistance directly.
The UN's World Food Programme has said it will ship one month's worth of food for more than 40,000 people to Madaya from Damascus, and enough for 20,000 people to Foua and Kfarya from the city of Homs.
Syria's Sana news agency reported that a rocket, presumably fired by rebels, hit a residential neighbourhood in the northern city of Aleppo, killing three children and wounding two other people. It said the Syrian army had begun a major offensive in the countryside to the west of the city.