That left a handful of seated protesters, including a mother from Colombia and her 22-year-old son, leading chants with a bullhorn and praying the rosary in bitter cold.
"We are here to put an end to the deportations that tear apart our families," said the son, Miguel Andrade, a youth organizer for the immigrant-rights group Juntos, which has chapters in Philadelphia and Norristown and sponsored the demonstration.
Andrade said he was about 10 when his father was deported to Colombia. He and his mother, Maria Serna, were left behind. They have green cards but the family is shattered.
The sit-in followed the demonstrators' march from Logan Square, where Salvador Sarmiento, a national organizer who came from Washington, told the group: "We are all from different walks of life. But today we walk together in a procession against deportation and raids."
After the demonstrators refused police orders to leave, a garage door was raised and a convoy of cars, including at least one van driven by a man in a police-style uniform, exited onto Callowhill, skirting the protesters by taking a path that led briefly across the sidewalk.
The Philadelphia demonstration was similar to actions this month in Elizabeth, N.J., and other cities.
It is part of a growing national movement by organizers impatient with President Obama and the failure of Congress to enact comprehensive immigration reform.
The Senate in June passed a bill with bipartisan support that includes a 13-year pathway to citizenship for many of the country's estimated 11.7 million undocumented immigrants. Immigration efforts in the House are stalled.
Said Sarmiento: "If the president doesn't stop the deportations, if the Congress doesn't do anything to stop them, we are going to stop them."