VATICAN CITY — Pope Francis prayed on Sunday for victims of violent protests in the west African nation of Gabon, calling attention to what he described as a “grave political crisis” in the former French colony.

In remarks to the faithful in St. Peter’s Square, Francis on Sunday also encouraged the Gabonese people, particularly Catholics, to be “builders of peace while respecting legality, dialogue and brotherhood.”

Gabon was marked by violent protests after the results of an Aug. 27 presidential election were announced. The opposition candidate mounted a legal challenge, accusing the incumbent leader of fraud.

The opposition says as many as 100 people have died in the protests, while the government has put the toll at three.

Francis says he supports an appeal by Gabon’s bishops for all sides to renounce violence.

The current Gabonese leader, Ali Bongo Ondimba, has held power since 2009, after taking over from his father, Omar Bongo, who had governed the country since 1967. Critics accuse the Bongo dynasty of using fraud and intimidation to reinforce their grip on power, charges the government consistently has denied.