I received an offer letter from a university abroad, should I continue to interview locally until my visa application goes through? I have received an offer letter from a university abroad, which I am likely to accept. The country however has a very stringent immigration policy and a very complicated and lengthy visa application process. There is therefore a real chance that my visa application could be refused.

I have other interviews lined up and I know the usual procedure would be to notify the universities that I have received an offer. However, I feel like I ought to keep pursuing those jobs as a "safety net" because if my visa application fails, I'd effectively end up jobless.

Would it be unethical to go on with those interviews until I have received my visa?
You should definitely continue interviewing locally. I have personally seen several potential hirings fall apart because of visa issues. This is a real possibility.

Consider this: You would never stop interviewing until you have a sure, written offer on the table. Simply do not consider this offer to be sure, until visa issues are in the clear.