At least four people were killed when a lorry laden with explosives detonated in Tolima province, western Colombia, on Sunday, a local official has said.
A two-month-old baby girl was among the dead, Tolima governor Adriana Magali Matiz wrote in a post on X.
The lorry exploded near a military base in the town of Planadas, damaging a nearby hospital and several other buildings.
It is not yet clear who was behind the bombing, but armed criminal groups have recently stepped up attacks against the security forces in what appears to be retaliation for an offensive ordered against them by the new right-wing President, Abelardo de la Espriella.
De la Espriella was sworn into office in August after campaigning on a tough-on-crime platform.
In less than a month, he had put an end to peace talks with some of Colombia's illegal armed groups, negotiations which had been started under his left-wing predecessor Gustavo Petro.
"In my government, criminal will have no political status, no leniency, and no impunity," de la Espriella wrote in a post on social media at the time, external.
At the start of his presidency, Petro had advocated for a "total peace strategy", arguing that only talks could lead to an end to the violence perpetrated by Colombia's many armed groups.
But after repeated breaches of the terms of the negotiations, Petro put some of the peace talks on hold.
De la Espriella has gone further, expanding his crackdown on all of the country's illegal groups, including bombing their camps.
These groups have in turn stepped up their attacks on the security forces.
On Saturday, a police officer was killed and another six injured when a motorcycle rigged with explosives was detonated in southern Huila province.
President de la Espriella described it as "a cowardly terrorist attack".
There have also been a number of incidents in which illegal groups have used drones - rather than cars or motorcycles - to transport the explosives.
In one of them, carried out on 23 October, a marine infantryman was killed and four injured aboard a Navy boat in Cauca province.
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