ABUJA / LAGOS:Nigerian President Muhammadu Buhari on Thursday called for an end to street protests in the country, as authorities in the commercial capital Lagos struggled to enforce a curfew imposed to contain anger over a crackdown on anti-police protesters.

Gunshots rang out and smoke rose from at least two fires in the affluent Ikoyi neighbourhood on Thursday, witnesses said. A fire broke out in the district's prison, the state government said. Video footage showed a blaze in a shopping mall in another part of Lagos.

The unrest has become a political crisis for Buhari, a former military leader who came to power at the ballot box in 2015 and is commander-in-chief of the armed forces. Some protesters have said they feared a return to the dark days of military rule.

Violence in Lagos, Africa's biggest city and the commercial hub of the continent's largest economy, has escalated since Wednesday. Groups of young men and armed police clashed in some neighbourhoods following a shooting on Tuesday night in Lekki district.

Rights group Amnesty International said soldiers and police killed at least 12 protesters in Lekki and Alausa, another Lagos district. On Thursday the human rights group called for an "immediate and thorough investigation of allegations of unlawful killing and use of excessive force against protestors in Lagos on the evening of Tuesday 20 Oct. 2020."

The army has denied soldiers were at the site of the shooting, where people had gathered in defiance of the curfew.

Buhari urged youths to "discontinue the street protests and constructively engage government in finding solutions" in a televised address to the nation that marked his first public statement since the shootings.

But the president made no direct reference to the shootings, prompting criticism on social media.

Reflecting widespread surprise at the omission, ex-lawmaker Shehu Sani, a former member of Buhari's party, tweeted: "You ask for speech, you got the speech and now you are speechless."

Entrepreneur Adam Bradford wrote: "Is Buhari's memory so short that he forgot about the Lekki shooting?"

The protests against police brutality, which involved nationwide marches for nearly two weeks until the Tuesday shootings, were largely peaceful.

But some people committed vandalism and other criminal acts on the sidelines of the demonstrations, and both the authorities and protesters said they were not demonstrators. Buhari acknowledged this by referring to those who had "hijacked and misdirected" the peaceful protests.

The shooting of protesters has prompted a wave of criticism of Nigerian authorities and the behaviour of its security forces.

The UN Human Rights chief said there was "little doubt that this was a case of excessive use of force", while United States presidential candidate Joe Biden and former U.S. secretary of state Hillary Clinton both condemned the use of violence on the protesters.

A delegation of U.S. officials who were in Nigeria for previously scheduled meetings met the country's vice president on Thursday and condemned the "use of excessive force by military forces who fired on unarmed demonstrators in Lagos," a department of state spokeswoman said.

Buhari, in his address, encouraged the international community to "know all facts available" before rushing to judgment.

UNREST

Much of the unrest in Lagos in recent days has been concentrated in the mainland areas of the lagoon city, where young men have set up makeshift barricades to block roads. But the trouble spread to a wealthier part of the city on Thursday when a fire broke out at a prison in the upmarket suburb of Ikoyi.

Polly Alakija, an artist, said she saw men armed with machetes walking in a street near the prison, as smoke billowed from the building, while soldiers fired guns. She said the gunfire lasted for about two hours, ending at around 1 p.m. (1200 GMT).

A Lagos state spokesman later said the fire at Ikoyi prison was under control and armed officers were at the scene. He did not say how it started or comment on the reports of gunfire.

Video footage posted online and on local media showed a fire at the Circle shopping mall on the Lekki-Epe Expressway.

Several states in southern Nigeria have imposed curfews after two weeks of confrontations across the country between security services and protesters against police brutality - the West African nation's biggest wave of unrest since the end of military rule in 1999.

Oil-producing Delta state on Thursday said it would start a 48-hour curfew on Thursday.

Hours before Buhari's speech, National Security Adviser Babagana Monguno, speaking to reporters in the capital Abuja after a meeting with the head of state, said the president had directed all security agencies to operate within "the confines of legality" and "not to do anything that will aggravate the situation".

The security adviser said Buhari was very concerned about the unrest in much of the country and did not want a situation in which there was "anarchy."