Officials in Argentina say they have found two explosives at a theatre in the capital, Buenos Aires.
Authorities said they were timed to explode during an appearance by Alvaro Uribe, the former Colombian president.
The bombs were attached to a mobile phone with an alarm set for 4:30pm local time on Wednesday, when Uribe would have joined a post-speech cocktail with business executives and other important guests.
Al Jazeera's Lucia Newman reports from Buenos Aires.
