The Baltimore City Mayor's Office of Emergency Management said the crash involved two tractor-trailers and leaking fuel.
By 9 a.m., the crash was cleared, according to the Coordinated Highways Action Response Team.
Before the crash was cleared, drivers headed north on I-95 had to exit at I-695, according to a statement from the Baltimore City Mayor's Office of Emergency Management.
"Emergency response crews are on scene and have contained the leak and are preparing to tow the vehicles," the statement, issued just after 6:30 a.m., said.
"The closure and delays are anticipated to last into morning rush hour, and motorists are advised to take alternate routes into the area," according to emergency management. Suggested alternate routes included MD-295, I-895 and I-695.