Thousands are crossing into Colombia to buy food and medicine after Venezuela's embattled president reopened two border crossings that had been shut for almost four months.

Long lines of Venezuelans stood at two international bridges near the city of Cúcuta on Saturday waiting to have their documents checked by Colombian officials. Venezuelan border guards dressed in green uniforms helped to control the crowds.

The pedestrian border crossings were shut down by Venezuelan President Nicolás Maduro in late February after his political opponents tried to use the bridges to transport several tons of food and medicine into the country.

A Venezuelan man carrying a child on his shoulders lines up to cross the Simon Bolivar international bridge into Cucuta, Colombia, Saturday, June 8, 2019. Venezuela's President Nicolas Maduro ordered the partial re-opening of the border that has been closed since February when he stationed containers on the bridge to block an opposition plan to deliver humanitarian aid into the country. (AP PhotoFerley Ospina)

A Venezuelan man carrying a child on his shoulders lines up to cross the Simon Bolivar international bridge into Cucuta, Colombia, Saturday, June 8, 2019. Venezuela's President Nicolas Maduro ordered the partial re-opening of the border that has been closed since February when he stationed containers on the bridge to block an opposition plan to deliver humanitarian aid into the country. (AP PhotoFerley Ospina)

Most of the aid was donated by the United Sates but rejected by Maduro, who said it was part of a plot to strengthen the opposition.

Venezuelans wait to cross the Simon Bolivar international bridge into Cucuta, Colombia, next to Bolivarian National Guard officers, Saturday, June 8, 2019. Venezuela's President Nicolas Maduro ordered the partial re-opening of the border that has been closed since February when he stationed containers on the bridge to block an opposition plan to deliver humanitarian aid into the country. (AP PhotoFerley Ospina)

Venezuelans wait to cross the Simon Bolivar international bridge into Cucuta, Colombia, next to Bolivarian National Guard officers, Saturday, June 8, 2019. Venezuela's President Nicolas Maduro ordered the partial re-opening of the border that has been closed since February when he stationed containers on the bridge to block an opposition plan to deliver humanitarian aid into the country. (AP PhotoFerley Ospina)

Venezuelans line up to cross the Simon Bolivar international bridge into Cucuta, Colombia, Saturday, June 8, 2019. Venezuela's President Nicolas Maduro ordered the partial re-opening of the border that has been closed since February when he stationed containers on the bridge to block an opposition plan to deliver humanitarian aid into the country. (AP PhotoFerley Ospina)

Venezuelans line up to cross the Simon Bolivar international bridge into Cucuta, Colombia, Saturday, June 8, 2019. Venezuela's President Nicolas Maduro ordered the partial re-opening of the border that has been closed since February when he stationed containers on the bridge to block an opposition plan to deliver humanitarian aid into the country. (AP PhotoFerley Ospina)