By Isabella Cota
SAN JOSE (Reuters) - Costa Rica's communications chief resigned on Wednesday amid a scandal engulfing President Laura Chinchilla, saying he failed to properly screen a man who arranged for her to use a private jet and is under suspicion of using a false identity.
The attorney general's office is now investigating flights Chinchilla made to Peru and to Caracas for the funeral of late Venezuelan leader Hugo Chavez.
Costa Rica has no presidential plane so Chinchilla usually flies on commercial airlines or uses aircraft provided by other governments when making state visits.
"Under the circumstances, I feel the right thing to do is resign as communications minister," Francisco Chacon, who acts as Chinchilla's spokesman, told a press conference.
Chacon said Gabriel O'Falan, who had claimed to represent a Colombia-based oil company called THX Energy, had duped him when they met before Chinchilla's trip to Peru.
Mauricio Boraschi, Costa Rica's anti-drug commissioner, told the news conference that O'Falan was believed to be Gabriel Morales, a Costa Rican citizen born in Colombia.
It was unclear what, if any, link there was between THX Energy and Morales. Reuters called the THX Energy office in Bogota on Wednesday night, but no one was available for comment.
"I've been the one facing (the press), defending the validity of the trip, saying that the company was legitimate and maintaining that they were free of questionable activities," Chacon said.
The Costa Rican attorney general's office says it is investigating whether Chinchilla broke the law by using the seven-seat Cessna 525B Citation CJ3 aircraft.
Chinchilla's office issued a statement late on Wednesday, saying she felt "indignant at the deception Chacon was subjected to."
"The President ... will order actions in the coming hours to ensure such situations are never repeated," it added.
Costa Rica has an Illicit Enrichment Law, which includes penalties of up to eight years in prison for public officials who accept gifts worth more than a small amount.
"This is a first-class scandal that has shaken the country's public opinion," said Congresswoman Carmen Munoz of the opposition Citizen's Action Party.
(Writing by Gabriel Stargardter; Editing by Simon Gardner and Xavier Briand)