Something fishy going on around here

Something fishy happened in the market the other day, Every coin dropped around 10percent suddenly across the board and every on exchange.

Correct me if im wrong but i was under the impression that the prices go up and down depending on supply and demand. In other words if more buy orders come in and theirs not enough sell orders to fill the buys orders then the price would go up and price would go down in the reverse situation.

So here is the fishy part how did all of a sudden every coin get a wave of sell orders? Its not even possible, say i have 10 coins i have to go in and place an order one by one. This would take 5 mins at least for 10 coins. so 2000 plus coins all drop at the same time weird and nearly impossible.

The only thing i could use to explain it is trading bots, maybe so many people or the larger holders are using trading bots this would make it possible. But i dont think that many people are. Maybe because 90 percent plus of altcoins are built of Ethereum so if Ethereum drops they go down with the mother ship, even tho it shouldn't affect token prices.

The market seemed to of dropped on the back of a raid on one of South Koreans largest exchanges and mt Gox dumping a bunch on Bitcoin on the makets.

Let me know your thoughts or correct me if i got it wrong.