[world32]

No, don't tell them. Not because they will take it as a threat but because you will look quite silly if you do mention this. Recruiters scan LinkedIn for anybody that has even just a couple mention of the skills they are looking for and then send all the matches messages along if they're be interested in a new job.

If you had an actual job offer on the other hand then that would be a different story. Then you could reasonably say "I have had an offer for this much salary so please can you match that otherwise you are asking me to work below my market rate for you and although I like working here I don't think it's fair to ask that of me".

[avichalp]

Good advice. Also, if you have job offerers and you are not letting them know, but your colleagues are effectively communicating job offers they have, then they will be prioritised for a raise over you.