MEXICO CITY — The Honduran government imposed a curfew on Friday and ordered security forces to move against protesters blocking roads and bridges, escalating a political crisis over the disputed count of votes from the presidential election last weekend.

The announcement late Friday came after what began as peaceful demonstrations by supporters of the opposition candidate, Salvador Nasralla, turned violent in some places. The government said the curfew would go into effect for 10 days, during which time anyone found outdoors between 6 p.m. and 6 a.m. could be arrested.

The move by the government of President Juan Orlando Hernández, who is seeking a second term, prompted fears that he might try to find a way to stay in office even if the final vote count went against him.

Edmundo Orellana, a former justice and defense minister, said on Twitter that to issue such a decree while votes are being counted was “the same thing as a coup d’état.”