Riot police fired tear gas on Tuesday to disperse thousands of May 1 demonstrators in Honduras' capital staging an opposition-led protest against President Juan Orlando Hernandez.
Protesters were seen running to get away from the choking gas, including some carrying children who had been overcome.
Journalists estimated around 20,000 workers, rural residents, students and members of unions and associations took part in the march before they were confronted by about 1,000 riot police.
Protesters had yelled "JOH out," in reference to the president's initials, and: "In our country, Honduras, we don't want dictatorships."
The demonstration was organized by unions and the left-wing Opposition Alliance Against the Dictatorship.
Opposition leader Manuel Zelaya -- a former president ousted by the military in 2009 -- arrived by bicycle.
The opposition says Hernandez, a conservative backed by the United States, was illegitimately re-elected in a November 2017 vote marred by delays and alleged fraud.
At least 22 people died in post-election clashes, according to the UN.
Zelaya told the UneTV network that the police action against the protesters on Tuesday was "a demonstration of the weakness of the dictatorship."
The television station said similar May 1 marches in other cities in Honduras were also targeted by police.
May 1 sees traditional workers' demonstrations in Latin America, where the day is celebrated as an international labor holiday.
Demonstrators clash with riot police during a May Day protest demanding the resignation of President Juan Orlando Hernandez in Tegucigalpa on May 1st, 2018