ELDERSBURG, Md. — Dive crews were in the water and helicopters hovered over the sky Thursday night in Carroll County.
That's where a swimmer went missing in the Liberty Reservoir, off Deer Park Road approaching the Baltimore County line.
Search efforts got underway around 8:30pm before being called off around midnight.
A large emergency response blocked off the immediate area as crews deployed again Friday morning on July 4th.
WATCH: Search continues for missing swimmer at Liberty Reservoir in Carroll County
Carroll County Sheriff Jim DeWees told WMAR-2 News the missing swimmer is a 20-year-old Pikesville man, but was not yet ready to release his name.
The man's family, from New York, traveled in to help with the search.
DeWees said the man and two other people were swimming to a small island in the middle of the reservoir when he went under water and didn't resurface.

Swimming in the reservoir is prohibited as certain parts can get up to 70-80 feet deep.
"Regardless, we're using a ton of resources to try and find this individual," said DeWees.