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Security members protect Venezuelan President Nicolas Maduro after his speech was interrupted in Caracas, Venezuela, on Aug. 4, 2018. A speech by Venezuelan President Nicolas Maduro commemorating the 81st anniversary of the Bolivian National Guard was unexpectedly cut short after he was interrupted on Saturday. (Xinhua)

CARACAS, Aug. 5 (Xinhua) -- Venezuelan President Nicolas Maduro escaped unharmed from an attempted attack of explosive drones on Saturday.

The attack happened here during a speech given by Maduro to commemorate the 81st anniversary of the country's National Guard when the drones exploded near Maduro and his wife.

The live television transmission was then abruptly cut at 5:46 p.m. local time (2146 GMT).

Seven National Guard soldiers were injured and rushed to hospital, but the president was not hurt, according to Minister of Communication Jorge Rodriguez.

Maduro described the attack as an assassination attempt in a later televised address to the nation.

The leftist president blamed the attack on the far-right factions in Venezuela, the Colombian government and conspirators in the United States, saying they were responsible, according to his address.

Venezuela-Colombia relationship has been long strained by frictions between the two neighbouring South American countries, including border disputes and military concerns.

Maduro said in June that Venezuela's opposition camp "has the backing of a handful of traitors there in Bogota (the capital of Colombia)," adding that his country was "besieged by the northern empire" -- the United States.

However, Colombian Foreign Ministry on Sunday refuted Maduro's accusation, saying in a statement that "the claims that the Colombian leader could be responsible for a supposed assassination of the Venezuelan president sound absurd and lack basis."

In his nationally televised address, Maduro said that some of those involved in the attack have been arrested, whose identities are unknown yet, and the investigation is underway.

"I pledge to do justice," Maduro wrote in his twitter following the attack, adding that he is "more determined than ever" to "consolidate peace, tranquillity, development and prosperity."

The country's right-wing opposition groups have launched waves of protests in recent years designed to pressure the government to hold early presidential elections in a bid to oust Maduro, who took office in 2013 and now faces criticism for the flagging domestic economy.

Oil-producing Venezuela has been struggling with an acute economic crisis since crude oil prices crashed in the international market, affecting state coffers and government-run services, including electricity and water.