According to Venezuelan Information Minister Jorge Rodriguez, two explosives-laden drones were launched last Saturday in the direction of the stands in Caracas where Maduro was watching a parade. Seven members of honor guard were injured, the president remained unscathed.
The suspects may have been involved in funding, paying for hotels and otherwise supporting those who carried out the apparent assassination attempt in Caracas, the AVN news agency reported Thursday.
A total of 25 people are being investigated over alleged ties to the assassination attempt, the minister said.
Venezuela has already turned to Colombia and the United States with a request for extradition of suspects. Maduro has put the blame on the opposition and Juan Manuel Santos, who at the time of the attack was Colombian president. The Colombian authorities have denied Bogota's involvement.