Aberdeen fans displayed flares at Hampden ahead of their League Cup semi-final against Hibernian despite pleas from the SPFL and SFA not to bring fireworks to the fixture.
It comes after the recent fixture between Dundee and Rangers at Dens Park was temporarily halted due to pyrotechnics in the away stand.
The fireworks were visible in the Pittordrie side's end of the national stadium prior to kick off.
The SFA and SPFL previously joined forces to urge fans to enjoy the weekend's fixtures safely and not to endanger any fellow supporters by using pyro at Hampden.
A statement read: "Ahead of this weekend’s Viaplay Cup semi-finals at Hampden Park, the Scottish FA and Scottish Professional Football League call on supporters to enjoy the showpiece occasions in a safe and responsible manner.
"Given the increased focus on the use of pyrotechnics, we appeal to fans of all four participating clubs to enjoy the matchday experience at the National Stadium but to do so in a manner that does not endanger the safety of their fellow supporters, or that has the potential to disrupt the matches themselves.
"The use of pyrotechnics is illegal. That message has been reiterated in the strongest possible terms by the police and football safety authorities, and reinforced by the SPFL and Scottish FA, during operational meetings with the participating clubs this week.
"The safety, security and enjoyment of tens of thousands of fans who will fill the National Stadium this weekend is paramount and there will be a range of steps put in place to help identify anyone who transgresses, including additional security measures and CCTV surveillance.
"We ask for your help in ensuring the weekend action is memorable for the excitement and entertainment generated on the field and not for any unwanted behaviour off it."
