A protester holds signs aloft outside Macy's before the kick off of Black Friday sales in New York November 27, 2014.[Photo/Agencies]

FERGUSON - Tensions eased in the St Louis suburb of Ferguson on Thursday after two nights of violence and looting sparked by anger over a grand jury's decision not to charge a white police officer for fatally shooting an unarmed black teenager.

Protests also dwindled elsewhere in the United States as the Thanksgiving Day holiday and wintry weather kept many indoors.

In New York, where protesters had vowed on social media to disrupt the Macy's Thanksgiving Day Parade through Manhattan, at least seven people were arrested during the event, police said.

In California, about 500 people were arrested in rallies on Tuesday and Wednesday that shut highways in major cities.

About 90 of those protesters who were still in jail in Los Angeles on Thursday were ordered released by the city's police chief in time for Thanksgiving dinner, a police spokesman said, as long as they promised to appear in court.

The order did not apply to anyone with an outstanding warrant, nor to one protester who was arrested on Wednesday night for assault with a deadly weapon, the spokesman said.

Ferguson became the focal point of a national debate on race relations after officer Darren Wilson shot dead Michael Brown on Aug. 9. The US Justice Department is probing possible civil rights abuses, and President Barack Obama has called for reflection on the difficulties minorities face in the country.

The grand jury's decision on Monday not to charge Wilson sparked protests in Ferguson, and more than 100 people were taken into custody on Monday and Tuesday nights. Buildings were torched, stores looted and police in riot gear used tear gas to disperse crowds. Only two arrests were reported Wednesday.

At a Thanksgiving service at the Greater St. Mark Family Church, which has been a gathering point for activists and religious leaders, many offered appreciation for their blessings after a tumultuous week.

"We live in a country of laws. But there has to be a law that governs us all," said pastor Tommie Pierson.

Ferguson, home to about 21,000 people, is a predominantly black city where almost all the political leaders and police are white.

In the area around the police department that has seen some of the worst violence, a different scene emerged on Thursday. With no protesters in sight and a minimal police presence on a cold but sunny day, local residents boarded up stores to patch up broken glass and protect windows still intact.

Some, including families, painted murals on the plywood boarding while passing cars honked in support.