DEARBORN HEIGHTS (WWJ) – Authorities say a man armed with a knife was shot and killed by a security guard at the district court building in Dearborn Heights.

The incident unfolded Thursday morning at the courthouse, located along Michigan Avenue near Gulley Road, just west of Telegraph Road.

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The man — later identified by police as Mark David Henning of Dearborn Heights — walked into the building, side-stepped a metal detector and was trying to avoid going through a security checkpoint when he pulled out a knife and was matched by guards with guns.

“He confronted a district court security guard with a weapon,” said State Police Lt. Michael Shaw. “The security guards confronted the individual and the suspect was subsequently killed in the lobby.”

Shaw said authorities aren’t yet sure what Henning was doing at the courthouse.

“We’re vetting him through our information sources to make sure there’s no other incidents that he may be tied with in the immediate area,” said Shaw. “It’s going to take us quite a while to kind of look into his background, see what he’s doing, if he’s had information —  business with the court before, if he was upset about that.”

A witness described the suspect as a white man in his 40s or 50s who ignored numerous orders to drop his weapon. Jamal Collins, who was at the court taking care a ticket, told WWJ’s Laura Bonnell he was standing right behind the suspect, who had a “steak knife” in his back pocket.

“There wasn’t too much talking going on besides the cops saying ‘Drop the knife,'” said Collins. “I was thrown to the ground by the cops.”

Collins said a man who was with the suspect yelled “That’s my brother,” and mentioned that he might have been under the influence of cocaine. Police have not yet confirmed that information.

“The initial cop that shot the guy, he wasn’t trying to shoot him. He gave him every chance, he kept telling him to drop the knife,” said Collins. “He said it like 6 times and the guy never answered, never replied, just pulled it out and advanced toward him.”

Shaw said the guard involved is privately employed by the district court and is not involved with the police department or sheriff’s office.

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Everyone who was inside the building at the time of the shooting is now part of the investigation, which is being handled by Michigan State Police.

“We’re in the process of interviewing everybody that was inside the building at the time, so you can understand that’s a pretty lengthy interview process,” he said. “Basically, this is a crime scene and we’ve locked down a crime scene and those folks are part of that crime scene. As we interview them, they’ll be sent home.”

The building is equipped with security cameras and investigators will be looking over those tapes as they piece together exactly what happened.

“Video doesn’t tell everything, as we all know, so a lot of the information that we get, we’ll get from the people that were actually in the room at the time that actually saw it occur,” said Shaw.

When the investigation is complete, State Police said, the findings will be forwarded to the Wayne County Prosecutor who will decide if any charges will be filed.

A nearby middle school and high school were put under lockdown as the situation unfolded, but police stressed that there isn’t any danger to the public.

There are no other outstanding suspects, according to police.

Dearborn Heights resident Sherri Matthews was arriving at the courthouse around 8:50 a.m. as police were rushing into the building. She described the scene as hectic.

“There are two ambulances in front of the building. I’ve counted about nine to 11 unmarked police cars… officer’s have their vests on and as they’re walking away from their cars, they have their hands on their holsters. They were walking toward other officers and then heading into the building,” she said. “There were three officers that had huge guns that went running into the building.”

Matthews eventually drove to a Home Depot parking lot nearby to watch the action unfold.

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Sources talking to WWJ said the courthouse was expected to reopen on Friday.