Amid chaos and defiance, Venezuelan opposition faces off against security forces as Maduro digs in

A massive effort to break President Nicolas Maduro‘s blockade of humanitarian aid descended into violence and chaos Saturday across the string of border flash points — showing both the growing defiance of Juan Guaidó and the U.S.-backed opposition but also Maduro’s willingness to fight back.

In a day of fast-moving developments at various points, anti-Maduro crowds at a Colombian border town faced tear gas fired by Venezuelan units, cheered as dozens of Venezuelan security forces switched sides and tried to rescue desperately needed aid packages from burning trucks.

In all, 285 people were injured and 37 hospitalized on the Colombian side of the border, according to Colombia’s foreign minister. At least four were killed on the Venezuela-Brazil border after clashing with pro-government militias.

In the Venezuelan capital, Caracas, the embattled Maduro danced at a pro-government rally, mocked the United States and broke off ties with neighboring Colombia. Late in the day, Venezuelan navy vessels threatened to open fire on a ship carrying 200 tons of aid from Puerto Rico, Ricardo Rosselló, governor of Puerto Rico, said in a statement. He said he had ordered the vessels to abandon the area temporarily, decrying the threat as “unacceptable.”

“I’m very concerned with the information we’ve received about paramilitary groups and other irregular groups already at the border with the intention to spread violence,” said opposition politician Nora Bracho. “We have no doubt that there will be violence, absolutely no doubt.”

In defiance of a ban against leaving the country, Guaidó made a secretive trip to Colombia on Friday to lead the aid effort and meet with regional leaders. He suggested the Venezuelan armed forces had helped him spirit across his nation’s western frontier.

But he was also running the risk of being barred from reentry or arrested upon return.

The attention on Saturday remained focused on the single-largest staging ground for aid in Cucuta.

Organizers in Cucuta had called for “every available Venezuelan” to turn up Saturday morning at 8 a.m. and await further orders.

Many began to awake before dawn on a rocky ground of a camp set up for them and began moving toward arranged meeting points to join the effort.

“We’re betting everything on this,” said Ricardo Justo, a 24-year-old salesman from Caracas who traveled 27 hours on a bus with a group of 30. “We’ll do whatever they tell us to.”

Air-raid sirens on bull horns awoke the camp at 5:20 a.m., rousing them for a day of action. Folk music began playing. Kleibysad Saab, a 47-year-old Venezuelan from the state of Carabobo, lead a crowd in chants of “freedom” before offering a prayer.

“No man can close the doors that God has opened,” she said. “Here we go!”

The crowd roared an amen.

In the western city of San Cristobal, about 150 people divided in four buses were stationed at one of the points where the opposition called yesterday for residents to gather to be taken to the border. But around 35 soldiers with shields and a convoy were blocking the way, telling them they had orders to only let cars pass.

Three drivers decided to order people to leave their buses because they heard vehicles were being impounded en route. About 110 people began to walk up a hill toward the border, hoping they would get a ride on the way. But they were quickly blocked by armed guards, and began shouting “let us pass, let us pass.” Within minutes they were allowed to.

“They know which is the right side,” said Julián Pozo, 54. “They are suffering too.”

Many marchers wore white shirts that read “freedom for Venezuela.”

“I want to free Venezuela from this yoke. The abuse has to end,” said Asdrúbal Castillo, a 65-year-old farmer. “This is a historical moment. It’s either now or never.”