Police seized an illegal explosive material that is more powerful than TNT from a downtown residence Saturday afternoon, officials said.
Madison police said they were alerted to possible explosive materials in a downtown residence by the building’s maintenance and management team, according to the criminal complaint. Police were given pictures showing chemistry-type items including chemicals, a filtration system, beakers, a gas mask and possible fuse material.
MPD seized the materials from the residence on the 10 block of North Brooks Street just after 2 p.m. on Saturday after officers found items and documents indicating the manufacturing of an explosive device, officials said. Andrew T. Cockerham told police he used the lab to create homemade rockets to shoot off in an open land area near his home in Wauwatosa.
Cockerham had lab notebooks with plans that included “very detailed and sophisticated chemistry lab notes on making explosive-type materials,” according to the complaint. He also had erythritol tetranitrate, which is an illegal explosive that is 60 percent more powerful than TNT.
Cockerham told police he created the ETN to make his rocket go faster and farther, according to the complaint. He also said he created it to use in an experiment in which he was hoping to create a heavy body armor piercing round that he would make available to law enforcement if they would ever need it.
University of Wisconsin officials said Cockerham is a former student who studied chemical engineering.
Detectives are working to determine if there are other reasons why Cockerham would possess some of the materials that were seized.
Police arrested Cockerham on suspicion of possession of an explosive device.
Police have requested help from the FBI, the Dane County Sheriff’s Office Bomb Squad and the Wisconsin National Guard 54th Civil Support Team, according to the release.