Can Employer sack you when you are sick?

Quick question, can an employer sack you if you are out sick on illness benefit ? Or would you have a case for unfair dismissal ?
Thanks

It would depend of the reasons whether it was Unfair dismissal or not.

Yes, they can.

I should have been more specific, if you are sick due to an accident that happened on that job, has the employer got grounds to sack you

Others will probably say the same, but without more details, the answer is that it depends.

Ultimately, if you are not fit to fulfill your contract of employment (whether through work-related injury or not), the employer can terminate the contract.

Obviously it isn't as simple as that and would require due process and consideration of various aspects (extent of injury, ability to work, possibility of alternative work if injury is linked to a disability, etc), but as above, ultimately they can.

Of course, if the injury is linked to an aspect of misconduct/negligence and this is covered in a policy, there may also be grounds there.

simply though, there isn't enough information to give specific advice.