At 9 p.m. last night, subcontracted workers at airports in eight major cities across the U.S. walked off the job — including at Philadelphia International Airport.

32BJ Service Employees International Union claims that airport subcontractors like PrimeFlight and McGinn Security continue to pay wages below the city-mandated $12 an hour. The airport employees are not members of the 32BJ, but the union has routinely helped organize strikes on behalf of the workers.

Supporting @32bjseiu demanding better working conditions for our airport workers!! #Philadelphia pic.twitter.com/AnhFz2RJKn

— MariaQuinonesSanchez (@MariaQSanchez) March 31, 2016

Several City Council members are currently at the rally to support the workers.

Last December, Mayor Jim Kenney said he would ban subcontractors from operating at the airport if they did not meet the city’s wage standards.

The airport strike was scheduled to happen last week, but was postponed in light of the fatal terrorist attack at Zaventem Airport in Brussels.

#Philly airport workers on strike this morning because #PovertyDoesntFly pic.twitter.com/11bhE5xxxV

— 32BJ SEIU (@32BJSEIU) March 31, 2016

McGinn Security recently settled an legal case regarding its workers right to unionize. PrimeFlight employs about 4,500 employees at 49 airports across the U.S. and Caribbean, and is contracted for baggage handling by American Airlines at PHL International. Last year, PrimeFlight fired one of its employees allegedly for speaking out about unfair labor practices.

Other strikes are happening right now in New York City, Newark, Washington, D.C., Fort Lauderdale, Seattle, Chicago, and Boston.

TY @CouncilmanKJ @Mr4thDistrict @MariaQSanchez @Morgan_Cephas 4 standing w/ #PHL airport workers. #PovertyDoesntFly pic.twitter.com/ePqcRSZGbv

— 32BJ SEIU (@32BJSEIU) March 31, 2016