The picture is not entirely clear, but I suspect that those critters are not centipedes but rather garden symphylans, Scutigerella immaculata. They do feed on roots and can damage plants. They seem to be hard to get rid of, submerging the pot as WillC suggests might help. Here's a link to some more information:
http://ipm.ucanr.edu/PMG/r1085...
Do the pictures look right? They probably came in with soil or the plant itself, you didn't do anything to cause this infestation. I don't think they'd have any reason to leave the pot. Sounds like they can be a problem in greenhouses.
