•Colombians head to polls Sunday to elect a new Congress and select presidential candidates for the May election.
•Elections are held under high alert for political violence, especially in rural regions dominated by illegal armed groups.
•President Gustavo Petro raised concerns about election software, citing the 2022 legislative elections where his Historic Pact movement gained 390,000 votes after a recount.
•Over 3,000 candidates vie for 285 legislative seats, with 41.2 million citizens eligible to vote; the European Union deployed observers.
•Voters will also choose presidential candidates from three major blocs in primary-style contests, shaping the political landscape for the next head of state.