The sheriff's office said that "hundred and fifty local, state and federal law enforcement officers" had been deployed in the search and that federal authorities were looking into leads related to Jakubowski outside of the state.
Investigators discuss the manhunt for gun shop burglary suspect Joseph Jakubowski.
Police searching for a Wisconsin man considered armed and risky stepped up patrols on Sunday at churches near his home because of anti-religious views expressed in a manifesto he sent to U.S. President Donald Trump, officials said.
Janesville Police Chief David Moore and Rock County Sheriff Robert Spoden said the 161-page manifesto, handwritten by Jakubowski, is more focused on issues with religious institutions and government positions of authority than schools, but patrols will continue in all of those locations in Rock County.
The only area church to close Sunday was Bethlehem Lutheran Church in Sun Prairie.
Joseph Jakubowski reportedly broke into Armageddon Gun Shop on Tuesday and made off with several handguns and high-powered rifles, according to police. Investigators followed up on about 320 tips.
The scene comes from a 15-minute video shot before Jakubowski disappeared last week and subsequently released by Rock County Sheriff officials.
An acquaintance told authorities Jakubowski previously spoke of wanting to steal weapons and carry out an unspecified attack.
They say he also mailed his anti-religious and anti-government manifesto to President Trump.
Police also believe he may possess a bulletproof vest and military-style helmet.
The sheriff's office also released a video that appears to show Jakubowski mailing a package to Trump. Authorities say the package contained a 160-page manifesto that featured anti-government rants and "personal angst against anything other than natural law or rule".
"As the search for Joseph A. Jakubowski (M/W, DOB: 07/21/84, 5'10", 200 lbs, green eyes and brown hair) continues this Sunday night, investigators are continuing to work through the evening to attempt to locate this armed and unsafe suspect. A burned vehicle registered to him was found near the store.
The FBI says that they have increased the reward to $20,000 for information leading to the whereabouts of Joseph Jakubowski.