The top-polling body had issued a notice to Adityanath and asked him to reply by April 5.
Notably, Adityanath passed the comment when the Model Code of Conduct (MCC) was in force.
Backstory: Adityanath claimed Congress fed terrorists, Modi taught them lesson
While addressing an election rally in Ghaziabad, earlier this week, Adityanath spoke about the successes of Centre. He was seeking votes for Union Minister VK Singh.
He claimed Congress fed biryani to terrorists but "Modiji's Sena (Prime Minister Narendra Modi's Army) gives them only bullets and bombs".
The star-campaigner said Prime Minister Narendra Modi was breaking the spine of terrorists.
Commission isn't satisfied with Adityanath's clarification: EC
Adityanath's comment didn't sit well with Opposition parties including Congress and Trinamool. They approached EC to complain about the alleged violation of MCC.
Taking cognizance of the complaints, EC said, "The commission is not satisfied with Shri Yogi's clarification. Hence, Shri Yogi Adityanath is advised not to use matters related to the Army for political purposes and be cautious in the future."
Understanding the rule which Adityanath broke
To recall, the EC had on March 19 directed parties to not use Indian Army or their actions for their poll propaganda. Before that, the body had told parties they can't use pictures of armed forces for their campaign.
VK Singh didn't agree with Adityanath, retracted statement later
It's also important to note that VK Singh rebuked Adityanath's comments. Singh, in an interview, said those who say Indian Army belonged to one person aren't only wrong but "traitors".
However, when his statement got attention, Singh took a U-turn and claimed he was "misquoted". He said that the journalist may have "dozed off".
Subsequently, BBC released the uncut clip from the interview.
Watch: Singh downplayed EC's notice as well
#WATCH Union Minister General VK Singh on his reported remark on UP CM's 'Modi ke sena comment': Jo mujhe bolna tha bol chuka ab usko aur todo marodo mat. Yogi ji ne jo kaha hai aap logon ne usko bhi toda maroda hai. Election Commission toh 100 cheezon ke liye notice deta hai pic.twitter.com/WnCwIRwcVp