Medway publishing firm CPI Mackays has just completed the production and first print run of a new biography of veteran pop diva Madonna.

Publicists have billed the book as one of the most controversial titles to hit the bookshelves in decades.

Christopher Ciccone, brother of the US singer, who performed at Radio 1's Big Weekend event in May,detailed his relationship with his better known sibling in his recently published book, ‘Life with My Sister Madonna’.

The top secret printing job completed at the company's Chatham site was under a heavy publishing embargo and had to be protected 24 hours a day by a team of professional security personnel.

More than 20 security guards, some with dogs, patrolled each separate job component during production and security guards also protected the perimeter.

Completed copies were stored in a secure unit that was also protected 24 hours a day.

Working with publishing company, Simon and Schuster, CPI Mackays’ printing and production staff worked flat out to produce a significant and highly confidential number of copies for launch. Parts of the book have already been serialised in the Mail on Sunday.

General manager Ian Smith said: “CPI Mackays are delighted to have worked.. on the time critical and highly sensitive production of 'Life with my sister Madonna'.

"Due to the sensitive nature and strict publishing embargo it was necessary to implement a high level of security to prevent unauthorised access to it.

"The project was a complete success."