(CNN) -- At least 11 people were killed and 80 injured when a pipeline exploded in western Colombia Friday morning, local authorities said.
The blast happened in the city of Dosquebradas, in the department of Risaralda.
Health officials will take soil and water samples from the area to test the blast's environmental impact, authorities in Risaralda said in a statement.
Col. Gonzalo Londono, a police commander, told CNN affiliate Caracol TV that officials suspect an attempt to steal gasoline was the cause of the explosion.
"Unscrupulous people tried to drill into the pipeline to rob gasoline," he said. What followed was a blast and fire that affected at least 80 homes, he added.
Authorities were evacuating residents from three neighborhoods and searching homes -- some of which collapsed -- for additional victims.