Islamists belonging to the militant group Maute have telephoned a bishop to say they will execute the priest and churchgoers kidnapped this week unless the military called off its offensive against them, according to local media.

Mgr Elmer Abacahin of Cagayan de Oro told Mindanao's Gold Star Daily that the group had phoned Bishop Edwin dela Peña of Marawi city and told him the hostages would be executed one by one unless the government gave in to its demand.

The priest, Fr Chito Suganog, was kidnapped on Tuesday night along with at least a dozen worshippers and church workers.