Spam registrations and job listings

Spammers have suddenly started to register as employers on my job website, and post spam job listings. I have job listing moderation turned on, so none of the “jobs” have actually posted.

Not a huge amount so far, maybe 10 – 15 per day. Still, it’s annoying, and I’m concerned that it might become a much bigger problem.

Any possible solutions I can implement to prevent, or greatly alleviate, the problem?

Thanks,

Frank

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