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Taylor Kinney, who’s led Chicago Fire since its debut, was absent from the show on Wednesday.

A source close to the production of Chicago Fire confirmed to PEOPLE in January that Kinney would be taking a leave of absence from the series “to deal with a personal matter.”

On Wednesday’s episode titled “Damage Control,” Kinney’s character, Lt. Kelly Severide, was attending “the best arson investigation training program in the world.”

The actor did not appear in the episode, but his character’s wife Stella Kidd (Miranda Rae Mayo) felt his absence in their empty apartment.

NBC

According to Capt. Tom Van Meter (Tim Hopper) from the Office of Fire Investigation, the program was a last-minute opportunity that was too good for Severide to pass up. Even though Wallace Boden (Eamonn Walker) is upset that he lost one of his best firefighters, Van Meter reminds him that Severide joining the program doesn’t necessarily mean that he’s leaving the firehouse.

Severide’s departure from the fire department comes after last week’s episode, where Severide appeared to receive a concerning message about Van Meter. After showing his phone to his wife, Kidd then asked him what he was going to do about it.

Kinney’s character has gone on to become an integral part of the series, eventually going on to appear on the network’s many One Chicago franchise spin-offs Chicago P.D. and Chicago Med.