BOGOTA, Colombia (AP) — The Latest on Colombia's presidential election (all times local):

8:15 a.m.

Polls have opened for Colombia's presidential election, where voters are choosing between a young conservative lawmaker and a former leftist guerrilla as the nation implements a historic peace accord.

Colombians began gathering outside polling centers early Sunday to cast their ballots in a tense runoff between Ivan Duque and Gustavo Petro.

The vote comes at a crucial moment: A still-fragile peace deal with leftist rebels is being implementing and coca production is soaring.

The two candidates have presented starkly different views on Colombia's economic model and whether changes should be made to the peace accord.