Former Costa Rican president Rafael Angel Calderon has been sent to jail for nine months pending an investigation into corruption allegations.
Calderon's detention came just days after the arrest for corruption of another former president of Costa Rica, a country known as Central America's most orderly and transparent.
Calderon, who was president from 1990-94, was detained on Thursday for questioning about a $39 million loan from Finland to Costa Rica in 2001 to improve public hospitals.
Under the Costa Rican justice system judges can sentence persons suspected of a crime to "preventative prison" while the case is prepared. Judges can also restrict individuals' movements in less drastic ways.
Calderon, 55, had left office at the time of the loan, but he retained links to power and helped broker the deal between the two governments.
He is accused of illicit enrichment and corruption.
Last Saturday, a judge put ex-president Miguel Angel Rodriguez, who briefly headed the Organization of American States, under house arrest for six months while he is investigated for bribery.
Rodriguez, who quit the OAS post on October 8 after just two weeks, is accused of taking a $550,000 bribe in a 2001 telecommunications contract. He was president from 1998 to 2002.
"I believe we will survive this crisis and that after this nobody will be eager to put their hands in the public till," said Costa Rican President Abel Pacheco, calling the measure precedent-setting.