selling holding sp down

What an interesting day for the SP. Every time it tried to get up, someone was selling down. It happened all day. It did really look like the price was purposely being held down. Hmmm.
Hate to be a conspiracy merchant, but is there a lot of shorting to hold the SP down for the big boys or is someone plainly manipulating the price in anticipation of a merger or buy out.
I asked these questions to the complaints section of ASX and they said they would investigate. Who knows! I'm a long term holder with crossed fingers.