Chicago police, the FBI and the Chicago Fire Department were at the condo building where 30-year-old Theodore Hilk lived.
Sources said police discovered two pipe bombs in a fridge inside a unit in the 200 block of East Illinois.
Officers obtained a search warrant and returned to the site Friday, where they found more "chemical compounds," Chicago police said.
Hilk was found dead inside his unit earlier this week, and when police went back, they found materials to make three different types of bombs and azide, a chemical used as a detonator.
A search warrant is being conducted on everything inside the condo.
FBI agents are looking for anything to help explain what the Kansas native was doing with the explosives.
FOX 32's Tia Ewing says what we know about Hilk so far is that he fell off the radar back in 2015. He did work for a company called Headlands Technologies in Chicago as a daytrader.
He also scored a perfect ACT score back in 2007, and is a graduate of MIT.
The cook county medical examiner will determine how Hilk died pending the outcome of the toxicology report.
In terms of the investigation, it continues.
The Sun-Times Media Wire contributed to this report.