A.J. Perez

USA TODAY Sports

The Dallas Cowboys’ plan to use a helmet decal as a tribute to the five police officers killed in last month's attack was denied by the NFL, according to a published report.

The league had already ruled that the Cowboys could not wear the circular “Arm in Arm” decal in the regular season. The Fort Worth Star-Telegram reported that the league also rejected a petition that would have cleared way for the Cowboys to use the decal in the preseason.

The Cowboys had unveiled the decal on the first day of training with Dallas police and city officials in attendance. The Star-Telegram reported that tight Jason Witten came up with the idea for the stickers.

The NFL did not immediately return a message seeking comment.