It happened at the intersection of Market Street and Schuylkill Avenue.
Organizers say it is part of A15, a worldwide economic blockade in solidarity with Palestine and calling for an arms embargo and an end to US taxpayer funding for Israel.
They also said the date is significant since Monday is Tax Day.
The protest began around 8:15 a.m. near Philadelphia's IRS building.
Meanwhile, Chopper 6 was above another protest a short time later, described as a "funeral procession" along key traffic routes in the city to "mourn" Palestinians killed in Gaza in the last six months.
Police appear to detain protestors disrupting morning commute in Philadelphia
For the latest traffic in your area, click here.