URENA: Locals look at a bus burnt on the eve during protests after President Nicolas Maduro's government ordered a temporary close-down of the border with Colombia, in the border city of Urena. - AFP

URENA:International pressure mounted against Venezuela's leader Nicolas Maduroyesterday, with Washington vowing to "take action" after oppositionefforts to bring humanitarian aid into the country descended into bloody chaos.Self-declared interim president Juan Guaido called on the internationalcommunity to consider "all measures to free" Venezuela after clashesat the border crossing left at least two people dead.

Guaido announcedhe would participate in today's Lima Group meeting of mostly Latin Americancountries in Bogota, and called on the international community to be preparedfor "all possibilities" regarding Maduro. US Vice President MikePence will represent Washington at the meeting. Secretary of State Mike Pompeosaid the United States "will take action" as he condemned violenceperpetrated by Maduro's "thugs." President Donald Trump has said thatWashington is not ruling out armed action.

Humanitarian aid,much of it from the United States, has become the centerpiece of the standoffbetween Maduro and Guaido, the 35-year-old leader of Venezuela's NationalAssembly who declared himself interim president one month ago. The country isgripped by a humanitarian crisis that has seen poverty soar during a prolongedrecession and hyperinflation.

Maduro claims theaid is a smokescreen for a US invasion, and has ordered several crossings onVenezuela's borders with Colombia and Brazil closed. Two people, including a14-year-old boy, were killed in clashes Saturday with Venezuelan securityforces that left more than 300 people wounded at various border posts.

Guaido had set aSaturday deadline for delivering food and medical aid stockpiled in Colombiaand Brazil. Hundreds of Venezuelans, many dressed in white, were frustrated intheir attempts to collect the aid at the Colombian border, where they werepinned back by Maduro's security forces. Trucks with aid were prevented fromentering the country, and force was used to keep out Venezuelan nationalstrying to cross in from Colombia carrying aid parcels. Colombia ordered aidtrucks to return from the border after the violence. International aid is alsobeing held on the Caribbean island of Curacao.

A ship with aidfrom Puerto Rico was forced to turn back after receiving a "direct threatof fire" from Venezuela's military, the governor of the US territoryRicardo Rossello said. He slammed the move as "unacceptable andoutrageous." Canada, a Lima Group member, called on Maduro to allow"safe and unrestricted access" for the humanitarian aid, and said itwas "deeply concerned" by the violence "allegedly perpetrated bythe Maduro regime" aimed a blocking the entry of aid. These attacks are"simply unacceptable," read a statement Saturday signed by theministers of foreign affairs and international development.

Violent clashes

Since dawn,protesters in the border towns of Urena and San Antonio were kept at bay by theVenezuelan National Guard firing tear gas and rubber bullets. Gunshots could beheard in the streets of Urena during hours of rioting. Civil defense officialsin Colombia said at least 285 people had been wounded in clashes at borderbridge crossings.

But the mostserious incident came hundreds of miles (kilometers) away, at the Santa Elenade Uairen crossing point on the southern border with Brazil where the killingstook place. Another 31 people were wounded when Venezuelan troops opened fireon civilians hoping to collect aid across the border with Colombia, accordingto rights group Foro Penal.

Maduro'ssupporters also halted and set ablaze two trucks loaded with aid driven throughbarricades on a border bridge, sending a pall of black smoke into the sky overthe Santander crossing linking Cucuta and Urena. Two other trucks carrying aidsent by Brazil to Venezuela returned to the Brazilian city of Paracaima afterVenezuelan troops barred them from crossing for several hours. Some VenezuelanNational Guard troops however took advantage of the confusion to abandon theirposts and cross into Colombia. Guaido has offered amnesty to all securitypersonnel switching sides.

Colombia'simmigration service said at least 60 members of the armed forces had desertedthe "Maduro dictatorship" by late Saturday. Guaido -- recognized asinterim leader by more than 50 countries -- formally launched a long-planneddistribution operation at a warehouse at the Tienditas border bridge in Cucutajoined by the presidents of Chile, Colombia and Paraguay.

Maduro defiant

Angered byColombia's support for Guaido, socialist leader Maduro announced that Caracaswas severing diplomatic ties with Bogota, and gave Colombian diplomats 24 hoursto leave the country. "I will never bow down, I will never give in. I willalways defend our country with my own life if necessary," Maduro told arally of his supporters in Caracas, after thousands had marched through thecity under the slogan "Hands off Venezuela."

At a separateCaracas rally thousands of government opponents, mostly dressed in white,marched waving flags outside the La Carlota military airport. As many as300,000 Venezuelans are in dire need of food and medicine after years ofshortages and malnutrition, according to Guaido, who has accused Maduro ofrigging his re-election and is demanding a new vote. United Nations figuresshow that 2.7 million people have fled Venezuela since 2015 and around 5,000Venezuelans emigrate each day. - AFP