Baltimore has lifted an overnight curfew imposed after riots sparked by the death of a black man in custody.

National Guard troops are now pulling out of the city. The curfew was put in place on Tuesday, after protests over Freddie Gray's death turned violent.

Six police officers are facing criminal charges over the death, which has been ruled a homicide. They deny wrongdoing.

Gray was arrested on 12 April, and died a week later from injuries sustained in the back of a police van.

Under the curfew, residents were ordered to stay home from 22:00 until 05:00, and officials had been expected to keep it in place for another day.

But on Sunday morning, Baltimore Mayor Stephanie Rawlings-Blake said she did not want to maintain it any longer than was necessary.

"My goal has always been to not have the curfew in place a single day longer than was necessary," the mayor wrote on her Twitter account. "I believe we have reached that point today."

Protests in Baltimore have continued since looting and arson erupted on Monday night - which prompted the deployment of the National Guard. However the demonstrations have been largely peaceful since then.

Maryland Governor Larry Hogan said the state of emergency in the city would not be lifted until the last soldier had left.

Correspondents say the charges against the officers - ranging from manslaughter to second-degree murder - have eased tensions.

The charges were announced on Friday by the city's top prosecutor Marilyn Mosby. But a lawyer for the six officers insisted they had done "nothing wrong".

Police have admitted that Gray, 25, was not secured in the van by a seatbelt and that his requests for medical attention while being transported were denied.

Riot police advance on protesters and media during protests in the Sandtown neighborhood where Freddie Gray was arrested on April 30, 2015 in Baltimore, Maryland. Gray, 25, was arrested for possessing a switch blade knife April 12 outside the Gilmor Houses housing project on Baltimore's west side. Andrew Burton/Getty Images/AFP

Gray's death is the latest in a series of killings of black men at the hands of police in the US which have sparked rioting and national debate.

Police timeline of Freddie Gray's arrest on 12 April

08:39: Officers approach Gray and he flees on foot

08:40: Gray arrested on corner of Presbury Street, Sandtown

08:42: Police request a van

08:54: Van departs with Gray inside, conscious and speaking

08:54-09:24: Van makes a total of four stops between arrest and police station arrival

09:24: Van arrives at police station where officers request paramedics to take Gray to hospital