A suitcase bomb exploded near a town square where 5,000 children were celebrating Halloween, killing two suspected bombers and injuring 37 people, including two boys who were in a critical condition in hospital today, authorities in Colombia said.

A car bomb ripped open cars and storefronts in the administrative centre of Colombia’s Pacific port of Buenaventura, killing six people and wounding more than 30, authorities said.

Colombian guerrillas have offered to free an ex-governor, a former politician and four other hostages to help jump-start talks on a prisoner swap.

Colombian police today discovered what they called an ingenious drug trafficking tool - a fibreglass submarine capable of transporting up to 10 tons of cocaine.