From UK Gov Website: On 1 July the ELN guerrilla group issued a statement saying that they would enforce an armed shutdown of transport and commercial activity, between 0600 on Thursday 3 July and 0600 on Sunday 6 July, in the departments of Arauca, Boyacá, Casanare, Santander and North Santander. British Nationals are advised to exercise caution in those regions over this period. Those already in the region should avoid any disturbances that they encounter, and monitor local media and police reports.
Read more:
https://www.gov.uk/foreign-travel-advice/colombia/terrorism