I first kicked you earlier to let you remove any hacks you had (.. and because no admins were online to witness it), you were being shot at by two cops at reasonably close range and you took no damage (with ~100 ping, not lagging that much). After you had killed them both, I saw you jumping on the spot but frozen, as if you were in a menu. This is when I kicked you as it was clear to me that you were using hacks at the time.
I then let you be for a while when you came back and turned to spectate you again after someone brought it up in the chat. Again, suspicious behaviour with taking no damage.
I decided to test it myself at an opportunity where you weren't moving (to remove any lag arguments, even though SA:MP doesn't account for lag through shooting anymore) and I managed to shoot 50 M4 bullets into you (whilst you were still) and you took 0 damage. Once you realised what I was doing I saw you jumping on the spot again, like before, so I presumed you disabled what ever you were using, I then shot you with a deagle and you took damage immediately when you weren't moving.
That's why you were banned.