Drafting a mail to warn the employees - taking leaves without intimation to HR department

Please help me in drafting a mail which is to warn the employees who take leaves without prior intimation to HR department and only convey to reporting manager by verbal communication and not following the rule for requesting and approval for leaves beforehand.
Thank you in advance

Leave is to be intimated to HR department? Why? It is okay if he is an employee of your HR department. Why should an employee of Finance department or Marketing inform you in advance of taking leave? If he has communicated the leave orally to his reporting officer, what is the issue? Who is the authority to approve a leave? Is it HR or the reporting Officer.Certainly, it is not the HR but the Reporting Officer is the authority to approve a leave. As such if he has communicated his leave of absence, there is no violation. You should first change the HR policy of your establishment and then start issuing memos/ charge sheets. HR department is not suppose to create a terror among the employees, rather should step in whenever there is anything wrong in the interpersonal relationship between the employees and employees or employees and their reporting officers etc. Don't say that HR is in the top of all and all should communicate everything to HR Manager. His role is not to command but to listen.

Mr Madhu rightly pointed out>
You can warn the employee those who are working under you and you are the authority to sanction leave.
In other case, HR can only issue the warning letter after receiving complaint from the DH of the employee if one is absenting from duty.

Dear friend,
Please let me know what is the set up and the reporting arrangement in your organisation. Depending on this only anything shall be appropriate to be suggested to you. Drafting a mail or a circular should be such that what administrative arrangement in vogue there.

Unity of command ought to be norm for good and effective management; multiplicity of command would result in inflated egos and all round confusion, esp. in an organisation having field functions.