The NFL made a "mistake" having photos of Pittsburgh Steelers linebacker James Harrison's hit on Cleveland Browns receiver Mohamed Massaquoi available for sale through its website and will take the photos down, spokesman Greg Aiello said Wednesday.

The NFL was selling this photo of James Harrison's hit on Mohamed Massaquoi before removing it Wednesday. AP Photo/Don Wright

Harrison was fined $75,000 for the hit. Pittsburgh television station KDKA first reported that the photos were for sale.

"We regret the mistake," Aiello said. "The photos will be taken down and we will ensure that no photos of illegal plays will be available again. An outside vendor uses an automated process to post photos for sale to fans. We will fix the process immediately."

Harrison said Wednesday morning he was aware of the photos.

"I guess they want to get their money on the front end and the back end," he complained in an interview with Sirius XM's "Mad Dog Radio."

The NFL is cracking down on illegal hits to the head, vowing to suspend players for infractions starting with this weekend's games.

In the past, players were either fined or ejected for illegal hits. However, after the series of recent flagrant tackles, several of which resulted in concussions, the NFL ramped up the punishment.

Football operations chief Ray Anderson indicated the suspensions could start immediately -- that is, involving play from last weekend's games. However, Aiello said the league wanted to give teams fair warning and would send a memo Wednesday, outlining the changes.