The Gunners star sustained the blow during their FA Cup third round defeat to Manchester United on Sunday.
A damaged ACL can leave a player sidelined for nine months to a year, meaning Jesus could not only miss the remainder of this season but a chunk of next campaign too.
Speaking on Tuesday ahead of the North London derby, Arteta said: "Yeah we know more now, and its not looking good at all. We need to review on more specialist."
Asked if it's his ACL, the Spaniard responded: "I don't want to confirm anything until we have the report."
Arsenal then released a statement later in the day to confirm the news about their striker.
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"Further to being substituted during our match with Manchester United on Sunday, Gabriel Jesus has received extensive assessments, scans and specialist reviews which have confirmed that he has sustained an injury to the anterior cruciate ligament in his left knee.
"Gabby will undergo surgery in the coming days and will soon begin his recovery and rehabilitation programme.
"We will continue to keep everyone updated with Gabby's recovery, with everyone at the club fully focused on supporting Gabby to ensure he is back to full fitness as soon as possible."
It's the second time that the Brazilian has suffered such an injury having damaged his right knee during the 2022 World Cup in Qatar.
However, this latest injury has affected his left knee, meaning that it's not a recurrence.
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Jesus lasted just 40 minutes of the weekend encounter against United as he went off after being involved in an awkward clash with Bruno Fernandes.
Tracking back to tackle the Portuguese star, Jesus fell to the ground and immediately looked in serious discomfort as the Arsenal medical team tended to him.
A stretcher then carried him off the pitch, with Jesus holding his hands over his face.
After the game, Mikel Arteta said of his knock: "No update, but it's not looking good.
"He was in quite a lot of pain, he had to come off on a stretcher and it's not looking good."
Jesus was a man in form before the injury.
Having only scored one goal this season until December 18, the forward netted six goals since, putting him in excellent form going into the second half of the term.
Jesus' injury blow is not good news for Arsenal, who already have a number of star players out.
Bukayo Saka is already sidelined until March after tearing his hamstring.
The winger, who has chipped in with nine goals and 13 assists this campaign, is already proving to be a big miss with Arsenal lacking creativity in his absence.
Ethan Nwaneri had emerged as Saka's replacement in the team, however, he's also going to be missing for a number of weeks after suffering a muscle injury.
Elsewhere, defenders Riccardo Calafiori and Jurien Timber are out with minor knocks.
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Fellow full-backs Ben White is also out for several weeks with a knee injury, while Takehiro Tomiyasu is another long-term absentee with a knee injury.
With Arteta's side currently six points behind league leaders Liverpool, they'll be praying for a bit of luck in the weeks ahead as they look to close the gap.
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