"He was just swimming having fun I guess," said Brianna Moore, who witnessed it.
"I really didn't know what was going on," said Dornesha Randolph.
"He was having some kind of mental episode," said Officer Thomas Wooten with the Houston Police Department.
WATCH: Naked nan swims In Hermann Park for hours
People crowded for a glimpse while officers and firefighters worked to get him out.
Wooten said when officers arrived the man was belligerent and started throwing his shoes and mud at officers.
After three hours of trying to talk the man out of the water, HPD said enough is enough. The dive team put a raft in the water and pulled the man onto it, then they took him to shore.
"We're going to take him to the hospital and get him evaluated. It's unknown if he was under any type of substance," said Officer Wooten.
While it's not know if the man was under the influence of drugs, Hermann Park has seen an increase in synthetic marijuana cases.
In just one day last month, 16 people at Hermann Park were treated for a possible overdoes of synthetic marijuana, also called Kush.
RELATED: Multiple people taken to hospital after possible overdose
Doctors say the drug is much stronger than marijuana and can lead to hallucinations, even death.
"We've seen a lot of people just frankly psychotic on this with violent behavior," said Dr. Mike Leath with the Memorial Hermann Prevention and Recovery Center.
The Kush issue has been so bad, the Mayor's office vowed to increase police patrols in the area. The initiative just started June 30th so an HPD spokesperson said it's too early to tell the progress of it.
RELATED: Houston Mayor puts focus on combating Kush epidemic
Again, it's not known if the naked swimmer was under the influence. That is something doctors will determine. Once he was pulled from the water, officers put a towel around him and took him to hospital to be checked out.