U.S. National Security Advisor John Bolton speaks about election security in the White House press briefing room at the White House in Washington, U.S., August 2, 2018. REUTERS/Carlos Barria

WASHINGTON (Reuters) - A senior White House official on Sunday denied the United States was behind a drone blast on Saturday during a military event where Venezuelan President Nicolas Maduro was speaking.

“I can say unequivocally there is no U.S. government involvement in this at all,” said John Bolton, national security adviser to the White House, told “Fox News Sunday” in an interview.

Bolton suggested that the Maduro government could be behind the explosion, citing widespread corruption and oppression in Venezuela.

“It could be a lot of things from a pretext set up by the Maduro regime itself to something else,” Bolton said, adding that there were no Americans injured in the blast.

“If the government of Venezuela has hard information that they want to present to us that would show a potential violation of U.S. criminal law, we will take a serious look at it,” he added.

Maduro often blames the United States, which has imposed sanctions against officials in his government, of “conspiracy” and blamed U.S. politicians of fomenting plans to topple him to end nearly two decades of socialism in Venezuela.

A little known group called the “National Movement of Soldiers in T-shirts” claimed responsibility for Saturday’s attack. Maduro was not hurt during the explosion.

Venezuela is suffering under the fifth year of a severe economic crisis that has sparked malnutrition and hyperinflation, which has caused tens of thousands of people to flee across the border into Colombia and Brazil.