Police arrested seven people in a drugs raid at a home in Anderby Close in Lincoln.
Armed officers were involved in the action as it was believed guns might be involved, but police said there was no danger to the public.
Superintendent Lee Pache said: “This warrant was based on information that the local community gave us about suspected drugs offences.
“Because of that we were able to carry out enforcement action today.
“A number of resources were involved in today’s warrant, including firearms officers because of concerns there may have been a firearm in the property where this warrant was executed.
“There is no risk to the general public.
“This is an active ongoing investigation and local residents will see police in the area for some time yet.
“We’re grateful for the patience of the community and ask that if you have any concerns please do feel free to talk to the officers in the area.”