Mites on my coriander plants

Hi,

I have recently noticed a load of mites on a few coriander plants I am growing, which have now spread to my runner beans.
The mites are very small, soem are green, some brownish/pink.
I've sqashed the ones I have found so far. Any idea what they are, and if the diluted washing up liquid method described in another thread recently would eliminate them?
Cheers
Steve