The Central Intelligence Agency posed a challenge to its followers on Twitter. The agency shared two seemingly identical photos and asked the internet to spot ten differences between the two. The challenge seemed reasonably easy, with many apparent differences between the two photographs.

It didn’t take long for people to locate all ten differences, but some eagle-eyed people managed to find more than ten. Numerous users found 12 differences, highlighting a missing logo on the BMW and graffiti that was erased from a wall. One person claimed to have found 14 differences.

The following day, the CIA praised those found more than 10 differences.

“How many did you find? If you found more than 10 differences, you practiced good tradecraft. Always look for opportunities to learn more,” the CIA captioned the tweet revealing the ten differences the agency was looking for.