US police have evacuated a suburban shopping centre in Colorado after the largest in a series of brawls that disrupted post-Christmas shopping around the US.
The trouble at the Town Centre mall in Aurora, Denver, was sparked when an arrest led to hundreds of young people converging on the site, with several fights breaking out, police said.
No one was seriously injured but five juveniles were arrested during the disturbance, Sergeant Chris Amsler said.
"As the officer was attempting to escort the arrestee to the Aurora Police Substation inside of the Town Centre, the crowd continued to advance on the officer and several other fights broke out," he said.
Police said they suspect postings on social media drew more people to the site.
"The crowd grew in size to approximately 500 people (mostly juveniles)," Sgt Amsler said.
Authorities shut down the mall as dozens of officers converged on the scene and worked to restore order. Sgt Amsler said fights continued as the crowd moved into the car parks.
Five people were arrested on charges including disorderly conduct, obstruction and resisting arrest.
Fights broke out at malls around the country, sending post-holiday shoppers scrambling for the exits and prompting numerous false reports of gunfire.
Police in Ohio said officers used pepper spray to disperse a large crowd following a fight at an upscale shopping mall in Beachwood, just outside Cleveland.
Police said the incident appears to have been "loosely organised on social media".
There were similar disturbances at malls in New York, Texas, and Memphis, Tennessee, where police arrested several people after fights at two malls.
There is no official word on whether any of the fights were connected.