They have had contact with Jakubowski before including an instance where he tried to take a weapon from an officer.
The University of Wisconsin-Rock County and Blackhawk Technical College were also closed.
"Whether it's the president or whether it's local officials or whether it's law enforcement, he basically has a dislike for anyone that has authority or governmental power", Spoden added.
Investigators learned from associates of Jakubowski that he has been highly agitated by national politics and recently mentioned a plan to steal guns and use them on to conduct an unspecified attack, Spoden said.
If the situation is resolved during the evening the district will be open as normal.
A $10,000 reward has been offered for information leading to Jakubowski's arrest.
Anyone who sees Jakubowski should call 911 or 1-800-CALL-FBI (225-5324).
New explosives found in Russia's St. Petersburg linked to metro bombing
His name was later confirmed by Russian investigators, who said he also planted a second bomb that did not explode. TASS said that the people living in the apartment were not the owners, but was unable to provide further details.
In a press release, the Rock County Sheriff's Office said 32-year-old Joseph A. Jakubowski, is wanted by authorities after a series of incidents that took place on Tuesday.
Jakubowski is accused of taking 18 guns from the Armageddon Supplies gun shop on Highway 14 Tuesday night.
The vehicle is registered to a Janesville man, Joseph Jakubowksi. Evidence of arson was found and it appears that the burglary and vehicle arson events are connected, according to the Rock County Sheriff's office. They've had to deal with him dozens of times but they say what he's accused of doing now does not follow his criminal patterns in the past.
"Basically, he's angry at all government officials", Rock County Sheriff Robert Spoden said at a news conference today.
A manhunt was underway Friday for a man suspected of stealing firearms from a southern Wisconsin gun store, threatening an unspecified attack that prompted several schools to close, and sending an anti-government manifesto to President Donald Trump.
Schools were notified of the threat, as well as other law enforcement agencies, including the U.S. Capitol Police and the Secret Service.