Roger
I largely agree with the above comments.
BUT
In a previous life I was an accountant and, at variuos points, studied law and particularly employment law.
Now, I would exercise a little control and look into the matter extremely carefully before taking any action. I have known people be taken to industrial tribunals for the most ludicrous charges, and found against because they had broken the most absurd rules.
eg:
An employee steals £15,000 from a company to fund his drug habit. Director finds out, sacks him on the spot. E'ee takes e'er to tribunal for unfair dismissal - relevant disciplinary proceedings had not been followed. Tribunal finds in favour of e'ee and awards £20,000 in costs. E'er CANNOT offset the £15k stolen from him - has to pay the £20k to e'ee, and seek recovery of the £15k as a separate legal action.
Absolutely crazy, I know, but true.
I am not saying you would be wrong to dismiss this e'ee, but just look into it first.
Cheers
Karl