The death of a 15-year-old boy meanwhile brought the death toll from weeks of protests to 43.
The death of a 15-year-old boy meanwhile brought the death toll from weeks of protests to 43 -- a dark milestone that matched the number killed in the last comparable wave of unrest, in 2014.
Looting and attacks against security installations erupted overnight in the state of Tachira, which borders Colombia, authorities said. The state prosecution service said on Twitter the boy was killed "during a demonstration" there.
"I have ordered the transfer of 2,000 guards and 600 special operations troops" to Tachira, Defense Minister Vladimir Padrino Lopez said on state television channel VTV.
Authorities said in a report on Wednesday that in Tachira some 20 shops, restaurants and a school were looted, two police stations set on fire and a military outpost attacked with firebombs over the previous night.
One military commander was hurt, it said.
Fernanda Carvalho, 53, told AFP virtually all the food was stolen from her bakery in San Cristobal.
"It felt like my world was falling in. There go years of work and investment," she said.
Clashes have erupted across the country during protests in anger at aduro's handling of an economic and political crisis.
The unrest has left 43 people dead since April 1, prosecutors say. Two of those people died in Tachira on Monday.
Protesters blame Maduro for an economic crisis that has caused shortages of food and medicine. They are demanding early elections and accuse him of trying to cling to power.
Maduro has accused the opposition of plotting a coup against him with US backing.
"We cannot call these demonstrations. These are subversive actions... which are now verging on armed insurgency," said Padrino, who as well as defense minister is also commander of the armed forces.
He accused the opposition of trying to start a civil war and wanting "to turn Venezuela into another Syria."
"We will not let the homeland fall into chaos," he said.
The UN Security Council was due to discuss the unrest in Venezuela on Wednesday, at the request of the United States.
"In Venezuela, we are on the verge of humanitarian crisis," US Ambassador Nikki Haley said in a statement ahead of the meeting.
"For the sake of the Venezuelan people, and the security of the region, we must work together to ensure Maduro ends this violence and oppression and restores democracy to the people."
Brazil is making contingency plans for a possible influx of Venezuelan migrants, Brazilian Defense Minister Raul Jungmann told reporters Wednesday.
But he said that "as a gesture of good will" Brazil would send back its ambassador to Venezuela. The envoy was withdrawn last year in a political row.
"We cannot lose any opportunity to help mediate" in Venezuela's current crisis, Jungmann said.
The government and the opposition have accused each other of sending armed groups to sow violence in the protests.
Police have fired tear gas and protesters have hurled rocks and Molotov cocktails in near-daily clashes.
Analysts say street protests are one of the few means the opposition has left to pressure Maduro.
Doctors and nurses in white overalls demonstrated in Caracas on Wednesday to denounce a crisis that has left hospitals desperately undersupplied.
"We don't want weapons! We want medicine!" they yelled.
Maduro fired health minister Antonieta Caporale last week after her ministry released figures showing infant deaths soared 30 percent last year.
Opposition groups planned two further rallies later on Wednesday evening.