The country’s leader was addressing the military in Caracas to mark the 81st anniversary of the Bolivarian National Guard of Venezuela.
He and the rest of the government escaped unharmed in what Information Minister Jorge Rodriguez said was an “attack” against the leftist leader.
Seven National Guard soldiers were injured, Rodriguez added.
Though AFP reported that firefighters at the scene disputed the government’s version of events.
“This was an assassination attempt, they tried to assassinate me,” Maduro later said in a televised address.
A little-known group called the “National Movement of Soldiers in T-shirts” claimed responsibility for the attack.
In a series of posts on social media, the group said it had planned to fly two drones but that snipers shot them down.
“We demonstrated that they are vulnerable. We didn’t have success today, but it’s just a question of time,” said the group, which says it was founded in 2014 to bring together all of Venezuela’s “groups of resistance”.
A Venezuelan who was visiting family close to the event in Caracas said she heard two explosions.
Photographs on social media appeared to show bodyguards shielding Maduro with black bulletproof panels.
â€śSeven National Guard soldiers were injuredâ€ť
Information Minister Jorge Rodriguez
Another snap also showed an injured military official clutching his bloody head and being held up by colleagues.
In footage on local TV, while Maduro was speaking about Venezuela’s economy the audio suddenly went.
He and others on the podium suddenly looked up, looking startled.
The camera then panned to scores of soldiers who started running, before the transmission was cut.
Maduro said “everything points” to a right-wing plot that initial investigation suggested was linked to Colombia and the US state of Florida, where many Venezuelan exiles live.
Several perpetrators were caught, he said.
The national guard was formed in 1937.
Writing on Twitter earlier in the day, Mr Maduro said: â€śI congratulate, in the framework of the 81st anniversary of the GNB, the men and women who make up this glorious component.
â€śTheir commitment and loyalty to keep peace have been proved in complex situations for the Homeland.”
Maduro, a former bus driver, won a new six-year term in May but his main rivals disavowed the election and alleged massive irregularities.
Maduro replaced former President Hugo Chavez after his death from cancer in 2013.
The self-described “son” of Chavez, Maduro says he is battling an “imperialist” plot to destroy socialism and take over Venezuela’s oil.
Opponents accuse him of authoritarianism, saying he has destroyed a once-wealthy economy and ruthlessly crushed dissent.
Venezuela’s once-thriving socialist economy has collapsed since the 2014 fall of oil prices.
Last year, rogue police officer Oscar Perez hijacked a helicopter and fired at government buildings in what he said was an action against a dictator.
Perez was hunted down and killed by Venezuelan forces in January.
A National Guard captain, Juan Carlos Caguaripano, early last year attacked a military base with a group of current and former military officials.
He was captured soon after.