Two other Baltimore men, Arthur Harris, 18, and John Maxwell Holland, 24, were arrested in downtown Hagerstown a short while later, Summers said.
The men were charged with possession with intent to distribute crack cocaine in excess of 50 grams, possession with intent to distribute crack cocaine, possession of crack cocaine and possession of drug paraphernalia.
Howell, Holland and Harris appeared in District Court on Thursday. Bond was denied for Howell; bond was set at $50,000 each for Holland and Harris. All were being held at the Washington County Detention Center.
Summers said agents also seized $385 in cash. He said the crack has a street value of at least $24,000.
Summers said NTF agents seized about 300 grams of crack and powder cocaine in March. But he said Wednesday's raid was one of the biggest this year.
"That's a significant seizure. That's almost a quarter pound of crack," he said. "We don't see that often."
Summers said authorities believe the suspects were dealing drugs in the Jonathan Street area. He said the investigation continues and further arrests are possible.