The spill occurred around 5 p.m. and caused vehicles and bicycles to lose traction on the roadway, Officer Gordon Shyy said.
All traffic was rerouted while the Department of Public Works and the fire department cleaned up the roadway.
Public works crews spread an absorbent along Howard Street and then street sweepers were sent in to clean the area before traffic could reopen, Shyy said.
Shyy could not confirm reports that the substance was diesel, and did not have information on the cause of the spill or any injuries.
