With record warm temperatures Friday night, police in Center City and North Philadelphia were forced to spend time dealing with crowds of teens that had some thinking back to last year's flash mob scares.

At one point, a crowd of teens walking on Chestnut Street west of Broad Street forced the Shops at Liberty Place to lock its doors at 6 p.m., CBS3 reported.

"Nobody was letting anyone come in or out because everyone was really, really nervous," customer Annie Perkins-Link told CBS3. "Security guards were everywhere and a lot of the store personnel were kind of scared."

Elsewhere Friday night, South Street was abuzz and police were scattered about as folks made their way outdoors to enjoy the exceptionally warm February evening.

SEPTA Police dispersed a large crowd of young people from the Broad and Girard subway station at about 10:20 p.m., but there was no confrontation and it was not a suspected flash mob, said SEPTA spokeswoman Heather Redfern.

Police monitored crowds throughout Center City and supervisors at the 6th and 9th Districts said officers had to disperse large groups of teens between 8 and 9 p.m.

Police said no arrests were reported.