Thousands of people have crossed to Colombia after Venezuela opened their common border to allow its people to buy food and medicine, officials say.
The frontier, closed by Venezuela last August as part of a crime crackdown, was to open for 12 hours.
Venezuela is going through a deep economic crisis and many say they struggle to feed their families.
Last week, about 500 Venezuelan women broke through the border controls in search of food.
Venezuelan President Nicolas Maduro ordered the border closure because, he said, the area had been infiltrated by Colombian paramilitaries and gangs.
The measure also prevents subsidised goods from being smuggled from Venezuela into Colombia.
Some 35,000 people crossed the border between San Antonio del Tachira, in Venezuela, and Cucuta, in Colombia, a Colombian official told the BBC.
'Happy to see so much food', By Natalio Cosoy, BBC News, Cucuta, Colombia
Supermarkets were crowded with Venezuelans buying basic supplies such as rice, oil, flour and sugar, which are expensive in their country because of the shortages.
Gloria Archila was all smiles. "They had everything," she said, comparing the situation here with the empty shelves in markets back home.
Everyone seemed to have a story like this - a mother who was looking for medicine for her daughter, another who described being "happy to see so much food together".
They complained about how devaluated their Venezuelan bolivar was, limiting their purchase power. They also found goods smuggled from Venezuela being resold here. But, by and large, as they returned home in packed buses, they were triumphant - and with full bags.
An unnamed woman who crossed with her husband and two young children told the Efe news agency it was "unfair" to keep the border closed.
"We are from San Antonio, and the reality is that we do not have any food to give to our children."
Venezuelans who want to cross into Colombia in states where the border has been closed need a special permit to do so.
But as the scarcity of food gets worse in Venezuela, many have crossed the porous border illegally.
What is behind the shortages?
- Venezuela grows and produces very little except oil and has historically relied on imports to feed its people
- Oil prices have plummeted leaving the government with a shortfall of income
- A lack of dollars means it is struggling to import all the goods its people need and want
- The socialist government introduced price controls on some basic goods in 2003 to make them affordable to the poor
- But up to 40% of subsidised goods were smuggled across to Colombia to be sold at a profit
- The opposition blames government mismanagement for the shortages
- The government says the shortages are the result of an economic war being waged against it