Internal auditor and Tax auditor

No it's not possible in the same year.

In one year you can't be a internal auditor and also the statutory auditor. However, in case you are the internal auditor for the last year, then for this year you can be the statutory auditor.

The internal auditor can not become the statutory auditor..

as per cooperative societies act, the same rules for statutory auditor are applicable to a cooperative society as are applicable to a company....

therefore, an internal auditor cannot be a stat auditor...........