Morales describes the alleged events in Santa Cruz
Bolivia's President Evo Morales says three foreigners have been killed after he ordered police to thwart a planned assassination attempt against him.
Security forces killed three alleged international mercenaries in the city of Santa Cruz, Mr Morales said.
He said intelligence reports had warned of an assassination plot by a group comprising foreign attackers.
Arriving in Venezuela for a summit, Mr Morales said two people had been arrested over the alleged plot.
Santa Cruz is a hotbed of opposition for Mr Morales, pictured
The three were killed in a half-hour shootout at the hotel in Santa Cruz, some 900km (620 miles) east of the capital La Paz, Mr Morales said.
"Yesterday, I gave instruction to the vice president to move to arrest these mercenaries and this morning I was informed of a half-hour shootout at a hotel in the city of Santa Cruz," said Mr Morales.
"Three foreigners are dead and two arrested."
He added that the alleged plot had been to kill him, Vice President Alvaro Garcia Linera and a cabinet minister.
There were conflicting reports about the nationalities of those killed, with some reports saying they were from Hungary while others said they were from Romania and Ireland.
Some police sources said there were Bolivians among the alleged plotters.
The two who survived were arrested and taken to the country's capital La Paz for interrogation.
Government sources said the group had links with extreme right-wing groups, associated with the opposition to Mr Morales' leftist government, says the BBC's Bolivia correspondent Andres Schipani.
Speaking in La Paz, Mr Garcia said the men had been carrying guns and grenades and attacked police as they were approached, adding that documents about the alleged assassination attempts were found after the shoot-out.
Earlier reports suggested unknown assailants had attacked the home of the Roman Catholic Cardinal Julio Terrazas of Santa Cruz with dynamite.
Interior vice minister Marcos Farfan said Wednesday's blast, which caused structural damage but no injuries, a "terrorist" act.
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