What does it mean when players say "kkkkk"?

[Kysto]

I've seen this a lot while playing in some of the servers. They usually say it after being killed in a cold way, like being headshot twice in a row. They'll go like, "kkkk".

Is it another way of saying, "You think you're pro, eh? Well, I'll stop beating around the bushes and start trying since you're so pro...."

I'm sure this is it, but I just wanted to make sure. lol