Forces loyal to the fugitive coup leader, Gen Lino Oviedo, tried to topple the Paraguayan government on Thursday night, driving tanks through the centre of the capital and blasting a hole in the Congress building before being persuaded to lay down their arms and be arrested early yesterday, the government said.
"The situation is totally under control. We are going to be relentless in applying the law to all those who have violated the law and the constitution," President Luis Gonzalez Macchi told a local television channel before dawn.
Gen Oviedo released a communique from his hiding place later yesterday, denying any involvement in the coup, but the language of his statement echoed declarations made by the coup leaders.
On Thursday night a group of light tanks filed past Congress in the centre of the capital, Asuncion, and blew a hole in the building's facade.
A Reuters correspondent then heard a burst of light arms fire before the tanks withdrew after an air force threat to attack the rebels.
Retired colonels and low-ranking officers who support Gen Oviedo seized control of the army's biggest armoured unit, helped by guards at the base on the city outskirts, the Defence Minister, Mr Nelson Argana, said.
A police unit also joined the revolt aimed at toppling the government in this notoriously corrupt, land-locked country of five million people. Paraguay's economy is bolstered by an enormous smuggling industry.
Rebels took control of the barracks at 7 p.m. (2300 GMT) on Thursday, but the revolt was all over by 2.30 a.m. (0630 GMT) yesterday, the government said.
It was the third time in four years that Paraguay's weak democracy has seemed threatened with a relapse into military rule. Each time Gen Oviedo, a former army chief, has been near the centre of events, and each time the United States, Brazil and Argentina have exerted pressure to ensure he does not succeed. Paraguay's neighbours in the Mercosur economic union have a particular interest in maintaining some semblance of democracy in this partner-state.
Security forces arrested a lawyer, a congressman, five retired officers and at least 25 serving soldiers. The head of the police, Casto Guillen, was fired.
"This is just the beginning. We have the constitutional right to rebel against tyranny," retired Col Vladimiro Woroniecki, a known Oviedo supporter, told reporters as he was led away under arrest.
The speaker of Congress, Mr Juan Carlos Galaverna, said documents found on the rebels showed they planned a long list of murders including Mr Macchi and Mr Galaverna himself.
An anonymous rebel officer had read a communique over the radio calling for Mr Macchi to step down to allow an immediate presidential election.
Mr Macchi, a former Senate leader, took over as president last year after Mr Raul Cubas, a protege and close friend of Gen Oviedo's, resigned after a week of violence following the assassination of the vice-president, Mr Luis Maria Argana.
The US affirmed its support yesterday for Mr Macchi after the attempted coup. "The United States strongly condemns the attempted coup that took place in Paraguay during the night of May 18th-19th. We reaffirm our strong support for the constitutional government of President Gonzalez," it said.