Authorities in Florida found a cache of guns and explosives inside a home during the course of a child pornography investigation Wednesday, officials said.
Deputies from the Pinellas County Sheriff's Office found a vast arsenal inside a locked closet in a home in Dunedin, including three explosive devices, 10 rifles, eight handguns, two shotguns, ammunition, a makeshift firearm sound suppressor, more than 15 knives, a baseball bat with protruding nails, a crossbow, brass knuckles and gunpowder, the sheriff's office said in a press release.
The deputies also found aerial photographs of a water treatment plant, an elementary school and a middle school -- all Hillsborough County -- as well as notes on how to make explosive devices, according to the sheriff's office.
A handwritten note found by detectives read, "The daughters come, and I am ready. I have fed on my hatred for centuries. My fury at those who imprisoned me shall be vast and without mercy. I shall have my bloody revenge, and then the WORLD WILL BURN BURN," according to the sheriff's office.
Officials arrested 24-year-old Randall Drake, who was transported to the Pinellas County Jail without incident, authorities said. Detectives attempted to interview him, but he refused to speak to them, according to the sheriff's office.
Drake is being held on $20,000 bond, but authorities said he would be taken into involuntary custody for a mental health evaluation even if he posted bond.
Two of the homemade explosive devices were constructed of metal cylindrical cigar tubes containing gun powder and wicks for detonation, detectives said. The third device was constructed with a plastic tube with gun powder insider and wrapped in tape with a fuse, officials said.
A bomb squad from the Hillsborough County Sheriff's Office safely removed the explosives from the home, authorities said.
Drake was charged with two counts of unlawfully making, possessing or attempting to make a destructive device, the sheriff's office said.
Drake has no criminal history or history of mental health issues, Pinellas County Sheriff Bob Gualtieri said at a press conference Thursday. Investigators went to the home -- where Drake lives with his mother and father -- to execute a search warrant in connection with a child pornography investigation, the sheriff's office said.
Gualtieri compared Drake's lack of criminal history to that of Las Vegas gunman Stephen Paddock, who killed 58 people and injured hundreds more after he opened fire on a crowd of concertgoers Oct. 1.
"These are the people that are most concerning to us, what we call the lone wolves, the sleepers who are out there, the people who are not on our radar," Gualtieri said.
Investigators will look into whether Drake was involved with anyone else or other organizations, but it appears that he was acting alone, Gualtieri said.
Authorities do not yet know what Drake planned to do with the items found in his home, Gualtieri said.
Drake bonded out of jail on Thursday evening. It is unclear if he has entered a plea or retained an attorney.
Officials did not comment on the status of the child pornography investigation or whether it is connected to Drake.
ABC News reached out to the Pinellas County Sheriff's Office for comment, but did not immediately receive a response.
ABC News' Ben Stein contributed to this report.