People demonstrate demanding Nicaraguan President Daniel Ortega and his wife, Vice-President Rosario Murillo, step down after deadly unrest

The United Nations said Tuesday that many deaths in nearly a week of anti-government protests violently repressed by police in Nicaragua may have been "unlawful" and called for an investigation.

The scrutiny from the Swiss-based UN human rights office adds to international alarm at President Daniel Ortega's ordered crackdown against a wave of anti-government demonstrations and clashes.

The European Union, United States and the Vatican have all urged talks to restore calm, while the US embassy in Managua ordered family members of staff out of the country after Ortega deployed the army to the streets and looting broke out.

A toll compiled from the Nicaraguan Center for Human Rights and Ortega's wife and vice president, Rosario Murillo, puts the number of deaths since last Wednesday at at least 27. Most were protesters, among whom university students and youths figure prominently.

"We are particularly concerned that a number of these deaths may amount to unlawful killings," Liz Throssell of the UN Office for the High Commissioner on Human Rights told reporters in Geneva.

"It is essential that all allegations of excessive use of force by police and other security forces are effectively investigated to ensure those responsible are held to account," Throssell said.

The UN office said at least 25 people, including a police officer, had been killed.

The protests were sparked Wednesday by pension reforms aimed at keeping Nicaragua's burdened Social Security Institute afloat by cutting benefits and increasing contributions.

But they rapidly spread and intensified as other grievances over Ortega's rule surged to the fore.

- 'Out! Out!' -

On Monday, tens of thousands of people -- employees, students, pensioners and ordinary citizens -- marched peacefully in the capital Managua and other cities demanding an end to the crackdown on protests.

Some groups called for "dictator" Ortega and his wife to step down, yelling "Out! Out!"

Ortega, a 72-year-old former Sandinista guerrilla leader who has ruled Nicaragua for 22 of the past 39 years, has been taken aback by the demonstrations, the biggest in his last 11-year stretch in power.

In a bid to calm the situation, he has canceled the pension reforms and called for dialogue, and on Tuesday authorities released dozens of arrested protesters.

The government also lifted a broadcast ban on an independent news channel which had been reporting on the unrest.

Ortega's wife Murillo, who days ago called the protesters "vampires," changed her tune to voice "faith that we are going to go forward united."

And lawmakers issued an unanimous call for "dialogue and peace," according to one ruling-party deputy, Carlos Lopez.

But there was no immediate sign that Ortega's security forces had been pulled back, and widespread anti-government sentiment persisted.

Nicaragua's business sector, whose support has shored up Ortega, has abandoned him over the days of violence.

A pro-government rally was being organized for Thursday to show that the president still enjoyed backing from part of the population.

- Coalescing anger -

Mass street protests are rare in Nicaragua, where the army maintains a tight grip on public order.

But dissatisfaction has been bubbling over in recent months.

Frustrations have been voiced over corruption, the distant autocratic style of Ortega and Murillo, limited options to change the country's politics in elections, and the president's control over Congress, the courts, the military and the electoral authority.

In rural areas, anger also stemmed from a stalled plan by Ortega to have a Chinese company carve a $50 billion canal across Nicaragua to rival Panama's lucrative Pacific-to-Atlantic shipping canal.

If the project went ahead, it would displace thousands of rural dwellers and indigenous communities, while dealing a blow to the environment.

- 'People want freedom' -

"People are demanding democracy, freedom, free elections, a transparent government, the separation of powers, rule of law. The people want freedom," former Nicaraguan foreign minister Norman Caldera told AFP.

"If the government doesn't yield, it's going to be very difficult to stop this (the protests)," he said, asserting that the "big majority" of the population was frustrated with Ortega.

"The repressive apparatus is not able to halt protests on this scale," Caldera said.

Story continues