TAMPA — Hours before his Northdale rental went up in flames, investigators say Patrick O'Brien, lead guitarist for the death metal band Cannibal Corpse, called relatives warning about "the rapture" and that "aliens have landed."

The next day, after the fire subsided, fire marshals found a large cache of weapon, locked safes and potential explosive devices inside the home the 53-year-old O'Brien rented at 16311 Northwood Dr.

PREVIOUS COVERAGE: Cannibal Corpse guitarist jailed in Tampa on burglary, assault charges

The stash included about 50 shotguns — including one with a barrel illegaly sawed off to about an inch past the stock — 10 semiautomatic rifles including a couple of AK-47 variants, two Uzi-style rifles and 20 handguns, according to a search warrant.

Authorities even found two flame throwers, according to the warrant, one inside the house and one outside of it.

The warrant reveals the backdrop to the chaos of that Dec. 10 night, when the Hillsborough County Sheriff's Office said O'Brien broke into a neighbor's house and then charged a deputy with a knife before he was repeatedly stunned with a Taser then arrested. Then his home caught fire, and firefighters had to retreat as the ammunition inside started to explode.

Rounding out what investigators said they seized from inside the charred home were thousands of rounds of ammunition — stored in boxes, military-style metal cans and even ammunition belts — several other weapons and weapons' parts and three skulls.

Local authorities called in federal agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives to help with the investigation. With the exception of the sawed-off shotgun, it is not illegal to possess such weapons. But the warrant does not say whether O'Brien had the proper paperwork for his cache.

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O'Brien's arrest report details how the chaos started: He entered a home in the 4700 block of Windflower Circle just before 7 p.m. O'Brien didn't know anyone at the home and didn't have permission to be there, the report said, but when the two residents inside the home asked him to leave he ignored them and shouted that "the rapture is coming."

Then he pushed a woman in the home to the ground and ran to the backyard, the report said. The couple called 911 and when deputies arrived they found O'Brien hiding behind a fence near the backyard. A deputy reported giving O'Brien "multiple commands" to surrender before he lunged at the deputy with a knife. O'Brien was stunned multiple times with an electroshock device, then handcuffed. Then flames were spotted at his house.

O'Brien was booked into the Hillsborough County jail on charges of aggravated assault on a law enforcement officer and burglary of an occupied dwelling with assault.

When O'Brien made his first appearance in court before a judge on Dec. 11, he was ordered to undergo a drug and alcohol evaluation before his release. That condition was removed on Dec. 12, records show. Then on Friday, he was freed after posting $50,000 bail.

O'Brien did not return calls for comment. His mother, Nancy O'Brien, declined to comment.

Cannibal Corpse was formed in 1988 in Buffalo, N.Y., and launched their career with an album recorded at Morrisound Studios in Temple Terrace. The band has released 14 albums, according to its website, with song titles such as "Bloodstained Cement" and "Icepick Lobotomy."

Last week, Andy Turner and Nikki Law from Cannibal Corpse's management team at Metal Blade Records declined to comment to the Tampa Bay Times about the incident.

O'Brien was arrested the day after the band announced it would be the opening act for legendary thrash metal band Slayer on the North American leg of their farewell tour. Cannibal Corpse band members and management have not commented publicly on how O'Brien's arrest could affect their spot on the tour.

Slayer's Final Tour is slated to stop at the MidFlorida Credit Union Amphitheatre in Tampa on May 10.

Contact Howard Altman at haltman@tampabay.com or (813) 225-3112 . Follow @haltman.