(Adds byline, details on tree lighting ceremony)
By Bill Rigby
SEATTLE, Nov 28 (Reuters) - Protesters angered by a grand jury's decision not to indict a white police officer for killing an unarmed black teenager in Ferguson, Missouri, entered a pair of shopping malls in downtown Seattle on Friday and disrupted a tree-lighting ceremony.
More than 120 people were marching when a group broke off, went through Pacific Place mall and chained shut two doors, Seattle Police Department spokesman Patrick Michaud said.
Seattle police later said on Twitter that a total of five people were arrested in the protests.
It was the latest in a series of demonstrations across the United States to disrupt Black Friday shopping at hundreds of stores. Some protesters called for higher wages at Wal-Mart Stores Inc while others protested over the death of 18-year-old Michael Brown in an August shooting.
In a protest targeting another Seattle mall, about 200 demonstrators entered the Westlake Center downtown and marched to a balcony where they chanted. They also disrupted a Christmas tree-lighting ceremony at the mall, with demonstrators setting off two fireworks during the event.
Spectators who came to see the Christmas tree outnumbered protesters, and while the ceremony was cut short there was little friction between the two groups.
Seattle police later said on Twitter the demonstrators left the mall to gather in a nearby park. (Additional reporting by Jimmy Lovaas in Seattle; Writing by Eric M. Johnson; Editing by Alex Dobuzinskis and Sandra Maler)