Officers led protesters away with their hands restrained Thursday. Police didn't return calls seeking details about the arrests.
A moratorium is in place, but it expires in October. The House of Delegates has passed a bill banning fracking. A similar bill is pending in the Senate.
Senate President Thomas V. Mike Miller has expressed support for a moratorium. On Wednesday, he said: "I'm favoring that fracking doesn't take place any time in the near future."
Gov. Larry Hogan hasn't decided whether to veto a fracking ban, saying he's waiting to see what the legislature decides.
Opponents cite pollution concerns. Supporters say fracking would create jobs.