The four people accused in a London, Ont., explosives and firearms-manufacturing investigation are facing a slew of new charges, according to court documents filed Tuesday.

Jerry Tong, Zekun (Alex) Wang, Fei (Frank) Han and Feiyang (Astrid) Ji now face an additional 19 charges in the matter, bringing the total number to 31 separate counts. Some are joint-charges, while others are individual.

Some of the newest charges include possession of five specific explosive substances, possession of stolen property and access to computer data related to making firearms.

The lengthy investigation goes back to Jan. 24 when police responded to an overnight trespassing call at the Western University, when two men entered one of the school’s engineering buildings.

Police arrested one person just outside the building, and an investigation led them to a house in the nearby University Heights neighbourhood where the other three were taken into custody.

Police completed a multi-day search of the residence at 212 Chesham Place, where Wang, Han and Ji lived, as well as two additional homes in Orleans, Ont., and Gatineau, Que.

All four of the accused were students or recent graduates of Western, with the three men having studied in the engineering department.

Firearms charges in other cities

When they were first arrested, all four accused received multiple firearms charges, including the manufacturing of a handgun and possession of a loaded restricted handgun.

New charges against Tong, Wang and Ji include the possession of magazines and suppression devices, as well as possession of another prohibited firearm. Tong and Wang are also now accused of handing and carelessly storing a rifle.

Tong, who faces the majority of charges, also has new counts related to events in other cities. He’s been charged with storing rifles at a home in Orleans, manufacturing a prohibited firearm in Ottawa and possessing a rifle at an unauthorized location in Quebec.

Court documents show that Tong held a firearms license, but some of his charges relate to possessing a firearm at a place not indicated on his license.

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Tong and Wang also face new charges related to events that happened months before their arrest. Wang is now charged with manufacturing a weapon between Sept. 1, 2025 and Jan. 24, 2026, while the pair are charged with breaking into a Western building on Oct. 9, 2025.

Explosive substances revealed

Court documents also show that Tong, Wang, Han and Ji face a new list of charges for possessing explosive substances, and names them for the first time.

They are accused of possessing pentaerythritol tetranitrate (PETN), trinitrotoluene (TNT), dinitrophenol (DNP), hexamethylene triperoxide diamine (HMTD) and lead azide.

Originally, all four were charged with possession of precursor substances and finished high explosives.

All four also face a new count of possessing property of Western University valued at less than $5,000.

Wang also faces a solo charge of accessing computer data that pertains to a firearm or a prohibited device, specifically design files capable of being used with a 3D printer, metal milling machine or similar computer system for the purpose of manufacturing a device.

Court process continues

In total, Tong faces 28 charges, Wang faces 20 charges, Han faces 11 charges and Ji faces 13 charges.

The four are continuing to make their way through the courts, with some still in custody and others out on bail.

Tong did not request bail and remains in custody. Han was denied bail and remanded back into custody in February.

Wang was granted bail in March under strict conditions, including 24-hour house arrest and constant supervision from two sureties, who each posted $200,000. Ji is also out on bail with no sureties.