What did those officers in Ferguson get hit with?

By now you're hearing about the two officers that got hit in Ferguson.  Some type of training is involved and the bullet placement sounds like something a protester (run of the mill protester) couldn't accomplish.  But thats my assessment of things.  What has my head spinning is the description of the wounds.  Officer #1 was hit in the face, the bullet traveled and stopped behind the ear.  Officer #2 was hit in the shoulder and the bullet exited his back.

A small high speed round?  Maybe a heavy grain 5.56 with a barrel with 1 in 12 twists?  Perhaps a 5.7x28mm round? Could it be a 22 cal hyper velocity bullet?

Something is off in these shootings.  I can't put my finger on it and much more info will come out but this sounds odd to me.