Molly Beck

Milwaukee Journal Sentinel

MIDDLETON - The gunman who shot four people at a Dane County software company Wednesday was flagged as being a danger to co-workers and banned from having firearms more than a decade ago, new police records show.

Anthony Y. Tong in 2004 was taken to a Sioux Falls, South Dakota hospital's mental health unit by police after a search of his home revealed a number of weapons and a large amount of ammunition — all of which we confiscated.

Described by South Dakota police as acting "paranoid" and "delusional" during the incident, Tong wouldn't tell police whether he would consider shooting anybody but said "there were people at work who were talking bad about him" prompting police to flag Tong as a danger to others.

Because the 2004 incident resulted in the revocation of Tong's concealed carry permit, Tong illegally possessed the 9mm pistol he used to shoot his co-workers at WTS Paradigm this week — including one person who was hit 10 times, according to a search warrant released Friday.

Though he wasn't supposed to have firearms, a search of Tong's Madison home this week revealed dozens of boxes of ammunition, a number of gun parts and accessories including a silencer, two firearms, a pellet gun, and three bulletproof vests, according to the search warrant.

During the August 2004 incident, Sioux Falls Police Department officers were called to Tong's apartment building after an alarm company alerted his landlord that Tong had disabled a fire alarm in his apartment, according to Minnehaha County Sheriff's Department records.

Police found Tong had disabled smoke alarms, ceiling lights, ceiling fans and anything attached to a wall or ceiling that was powered by electricity. Tong said he had disabled everything because "people in the apartment below him were eavesdropping on him."

Police said Tong was acting defensive, delusional and paranoid, and was carrying a loaded handgun with a double magazine, pepper spray and two knives. Police also found a Colt AR-15 rifle in the apartment and a large amount of ammunition.

Tong would not answer when asked if he considered shooting someone else, and put his head between his knees instead.

Neighbor: Tong kept to himself

Adam Limmer lived next door to Tong in southern Sioux Falls — not at the apartment building where police were called for the 2004 incident — for about four years. After Limmer moved in, he saw Tong outside and tried to introduce himself.

“He said, ‘No, that’s all right, we don’t have to,’ and backed away,” Limmer recalled. That was about the only conversation Limmer had with Tong.

Other than an older woman who sometimes came over to clean, Limmer said he didn’t recall seeing visitors. Tong would mow his lawn and blow snow from the sidewalks and driveway, but was rarely out.

“He just really didn’t want to be out in public much,” Limmer said. “He just kept to himself.”

Tong moved from South Dakota to Madison in 2017. Before moving to South Dakota in the early 2000s, Tong lived in Jacksonville, Illinois, where his father was a math professor at Illinois College until 1993.

Jacksonville Police Chief Adam Mefford said the department had no record of interacting with Tong.

According to Middleton Police Chief Charles Foulke, a federally licensed firearms dealer would have been aware of the revocation, but Foulke said at a news conference Friday that he did not know whether the 2004 incident also involved Tong's workplace and whether the incident would show up on a criminal background check.

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Motive still a mystery

Foulke said police are investigating the 2004 incident to determine whether it is connected to Wednesday's shooting in any way, but warned the public about connecting dots without more information.

"We must use caution in trying to jump to conclusions that this is a mental health shooting related incident," Foulke said, noting the South Dakota incident was 14 years ago.

"And also we need to be cautious that we don’t paint everyone with a broad brush of everyone with a mental health issue is going to become an active shooter, because as we know, that is not the case and that is not at all what we are trying to push out today," Foulke said.

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Foulke said police are still seeking information to understand why Tong decided to enter his workplace on Wednesday and shoot his co-workers at WTS Paradigm in Middleton, sending three to the hospital with injuries.

"He came to work that day and was working on a normal basis when this happened," Foulke said when asked whether Tong was disciplined or terminated before he opened fire.

WTS Paradigm issued a statement Friday, saying Tong was "in good standing" and not facing any discipline at the time of the shooting.

"We, like everyone else, are shocked and saddened by this senseless act," the statement said.

Difficulty tracing gun

The federal Bureau of Alcohol, Tobacco, Firearms and Explosives is attempting to trace the weapon Tong used but are having trouble doing so because the firearm is "unique," Foulke said. He would not provide more details.

Tong was killed in a shootout with police and Dane County sheriff's deputies. Foulke said police involved in the shooting are being interviewed Friday by the state Department of Justice's Division of Criminal Investigation.

Information about the police responsible for Tong's death will be released following the interviews, he said.

Names of victims will not be released at their request, Foulke said.

Authorities executed a search warrant late Wednesday at Tong's home in the 9700 block of Gilded Cider Boulevard, in a new subdivision under development on the far west side of Madison. Foulke said they removed items that were "beneficial to the investigation," but he declined to elaborate.

Foulke said Tong lived in the home alone and that no one else is believed to have been involved in the shooting.

Dane County Sheriff Dave Mahoney told reporters Friday the victims and Tong's co-workers are the heroes of the incident.

"Unfortunately earlier this week, Middleton joined the cities (and) communities across the world whose lives changed because of an active shooter incident," Mahoney said. "But we’re a vibrant community. We’re a healing community."

Jonathan Ellis and Danielle Ferguson of the Sioux Falls Argus-Leader contributed to this report.