TEGUCIGALPA, Honduras (AFP) — Police in Honduras fired teargas Monday at demonstrators who set up flaming roadblocks and looted stores after the incumbent president was declared the winner of a heavily disputed election.

The leftist opposition has claimed fraud in the election three weeks ago that finally led to the pronouncement Sunday of conservative President Juan Orlando Hernandez as the winner after an oft-interrupted vote count.

International observers also cited irregularities.

Protests broke out Sunday night and continued into Monday morning as police cleared the streets of barricades.

In the northern city of San Pedro Sula, police said protesters looted stores and burned a bank branch and a bus.

In the capital city Tegucigalpa, people woke up Monday to smouldering barricades of tires, sticks and rocks. Authorities sometimes needed heavy machinery to remove them. Under a light rain, some small groups of demonstrators continued to man roadblocks.

On a road leading out of the north of the city, police fired teargas at demonstrators and on a major thoroughfare they negotiated with protesters to leave one lane open to traffic. Hernandez’s leftist opponent in the election, Salvador Nasralla, left the country Sunday night for the United States to try to draw attention to what he said was ballot tampering in the November 26 poll.

There has been violence since the election, as anti-Hernandez protesters and police squared off repeatedly.

Police have counted three deaths in the unrest. But the opposition says 20 people have died, and Amnesty International registered 14 fatalities.

The ballot was deeply contentious.

Hernandez, 49, stood for re-election against Nasralla, a 64-year-old former TV presenter, despite a constitutional ban on presidents having more than one term.

His conservative National Party said that rule was scrapped by a 2015 Supreme Court ruling. But the opposition insists ballots were tampered with after the election, and says unusual breaks in the count that dragged out the tally over more than a week were suspicious.

The leftist opposition alliance said it was not recognizing Hernandez’s win.

The Supreme Electoral Tribunal had previously declined to name a victor, despite saying that its count of the ballots showed a slight margin in favour of Hernandez: 43 per cent to 41 per cent for Nasralla.

But it had to do so by a December 26 deadline, or risk the entire election being invalidated. Nasralla, the candidate of the leftist Opposition Alliance Against the Dictatorship, is standing firm on his claim that he won the election, and that only fraud made it look like Hernandez had the edge.

He is insisting the entire vote be held again, with greater international scrutiny. Honduras is beset by violence, poverty and corruption and provides many of the undocumented migrants headed to the United States.