The former director general of the Organisation of American States has been arrested on his return to his native Costa Rica.
Rodriguez was arrested on arrival in Costa Rica
Miguel Angel Rodriguez stepped down last week after being accused of accepting a bribe while he was the Costa Rican president.
He flew into the capital, San Jose, on Friday and was immediately detained.
He has not been formally charged but a judge has demanded that he testify about the allegations.
Mr Rodriguez had only spent two weeks in his job as OAS president before stepping down.
He was received by security teams at San Jose airport, handcuffed briefly and then driven away in a police van, according to the Associated Press news agency.
"I am calm, I am not afraid," he told journalists during the flight.
"I have come back to defend myself and prove my innocence."
Mr Rodriguez was Costa Rican president from 1998 to 2002.
The corruption allegations centre on a contract awarded to the French telecommunications company Alcatel in 2001.
Mr Rodriguez says he received $140,000 from a former head of the country's power and telephone company, Jose Antonio Lobo.
Mr Lobo says he gave the former president $150,000 - a portion of a $2.4m "prize" arising from a mobile phone contract worth $149m which was won by Alcatel.
But Mr Rodriguez says the money he received from Mr Lobo was a loan intended to help finance his campaign to head the OAS.
His successor as Costa Rican leader, Abel Pacheco, had urged him to resign as OAS head and clear his name.