Per 
Special Containment Procedures: Sightings of SCP-X are to be recorded and cataloged as per standard observation procedures. As SCP-X is effectively self containing, attempts to stop media attention regarding specimens similar to SCP-X are likely to be more detrimental to its containment than simply recording them, and as such should not be attempted.
Media attention regarding sightings of SCP-X are to be removed from circulation by Foundation web crawlers. Absolutely no new research is to be pursued into SCP-X as of 17/02/1973 and all current information regarding SCP-X is to be contained at Site-██ with access restricted to O5 discretion.
Description: SCP-X instances are small to medium seized canines of differing phenotype, one of the only physical similarities between instances being a resemblance to members of the genus Vulpes and smaller Canina. Although not outright undetectable, instances of SCP-X are incredibly hard to perceive, with only those fully aware of their existence and presence in the immediate environment having the capability to distinguish them from their surroundings.
SCP-X are known to frequently use their ability to steal loose objects from populated areas without being detected, despite usually working as individuals, they have been seen to work in complex teams of 2-30 if necessary. Items taken by SCP-X instances are not random, they will specifically hunt for articles of information such as books or disk drives. If successful in retrieving such an item, instances will make their way underground, usually through sewer systems, subways or previously dug holes and remain dormant for several weeks.
The exact population of SCP-X is unknown however Foundation estimates range between 500,000 and 50 million. Until recently it was believed that SCP-X was present on every continent other than Antarctica, however in 1958 a deceased specimen was discovered at the site of Discovery Hut, buried under several meters of snow.
Addendum:
Deleted Files:
Expedition XXXX-A - 05/01/1972
Status: Contact Severed prematurely
Rescue Expedition XXXX-B 03/02/1973
Status: Contact Severed prematurely
Video files: Deleted
Files pending deletion:
05/01/1987
Today marks the anniversary that expedition vanished into thin air, not a trace of them was left, almost as if they wanted to stay hidden.
Finding out what happened was apparently only on the council's mind for about five minutes, the moment the second expedition team is announced, myself and everyone else is booted from the project. It's not just about loosing that cushy job, I'm a field researcher after all, it's about finding out the unknown, is that not our entire purpose?
Well I think it is. This is honestly been on my mind for the past decade or so and I've finally managed to get under their noses. I've put a team together, told them its a sanctioned venture into some hell hole as is usual for them, grunts don't ask many questions. We're heading out to where we sent that expedition tomorrow, Alexandria, the ancient city of sand and more sand.
07/01/1987
I knew they were crap but jeez, my tooth just cut clean through one of those little travel toothbrushes.
- Richard.
