The United Nations, European Union and United States have urged Honduras to investigate the "violent" deaths of six young women in just four days, including a nurse who died in police custody.

Honduras police said Keyla Martinez, 26, was arrested on Saturday night for violating the coronavirus curfew in La Esperanza in the country's west, and claimed officers found her in her cell hours later "trying to kill herself".

The hospital she was brought to said she was dead on arrival, and prosecutors said an autopsy showed Martinez had died from hanging.

But the Anticorruption Coalition of civic groups has urged the authorities to bring to justice "those responsible for the violent death of the young nurse" so that the crime, like "90 percent of murders of women" in Honduras, does not go unpunished.

And Amnesty International has called for a "prompt, exhaustive, independent and impartial investigation into Keyla's death" and urged authorities to end "the excessive use of force against those mourning this human loss and demanding justice" in recent protests.

Nurse Keyla Martinez, 26, died after being arrested on Saturday for allegedly breaching a coronavirus curfew in Honduras
Nurse Keyla Martinez, 26, died after being arrested on Saturday for allegedly breaching a coronavirus curfew in Honduras AFP / Orlando SIERRA

In a joint statement late Thursday, the UN and the EU delegation in Honduras said they "urge the authorities to carry out actions aimed at clarifying these facts and all those linked to any form of gender violence, in a thorough, impartial, expeditious and transparent manner."

They said violence against women and girls has increased during the Covid-19 pandemic, and listed the names of six, including Martinez, who died a "violent death" in the previous four days.

The US embassy in Honduras tweeted it had spoken to Honduras' Interior Minister about the Hernandez case, and called for "prompt and exhaustive investigations in all these cases."

Honduras police said the officers on duty on the night of Martinez's death were placed under investigation.

According to the National Autonomous University of Honduras' Observatory on Violence, 6,045 women have been killed in the country in the last 16 years, 30 so far this year.