Thousands of protesters in Venezuela's capital have been demonstrating against the country's president Nicolas Maduro whose government is being blamed by many for economic problems and food shortages.

However supporters of Maduro are also rallying in huge numbers and the government accuses the opposition of trying to mount a coup.

"There is no food. There is no paper. There is no medicine. We are dying," protester Maria Alvarez told CNN. "Please, help Venezuela. This has to end. Maduro, you have to understand that your time is up."

Demonstrators packed three major avenues in the capital, filling plazas and roads. Dressed in white clothing, the throng danced, sang and waved Venezuelan flags as they marched along, calling for a referendum to oust him from power.

On Thursday (1 September) there were tense stand-offs as riot police stood in lines facing the demonstrators. There were reports of clashes on social media between police and demonstrators on the Francisco Fajardo Highway at Las Mercedes.

According to A Todo Momento 40 demonstrators were arrested by the Bolivarian National Police (PNB). Opposition leader Henrique Capriles spoke to the demonstrators saying that government officials had tried to stop people from joining the protests. Capriles lost by a narrow margin in the 2013 election following President Hugo Chavez's death.

"Maduro is afraid! The more obstacles there are, the more people will peacefully be in the streets!" Capriles wrote on Twitter.

"This country that has so many natural resources is living through the worst poverty," he said.

The march on 1 September is the first in a series of protests demanding a referendum. Maria Corina Machado, a strong critic of Maduro, tweeted: "Today in the streets we demonstrated that a new phase of the fight has begun. The transition is urgent and inevitable."

"We're hungry in Venezuela. We can't stand it anymore," one protester named as Antonio told NBC News. "We're dying because of criminality and shortages. We need just one thing: the recall referendum to fire Maduro."

Experts predict Venezuela's economy will shrink by 10% this year, while inflation will rise to 700%.