PUBLISHING company Bloomsbury said that a magical performance from child wizard Harry Potter in the first half of the year helped it to one of the busiest six-month periods in its history.

The London company, reporting financial figures for the six months to June 30, said the fifth instalment in the life of JK Rowling's schoolboy character ensured the publishing phenomenon continued to grow.

The release of Harry Potter And The Order Of The Phoenix also helped to increase sales of the previous four books, helping lift group sales 18.2 per cent in the half to £29m.

Bloomsbury said pre-tax profits increased 13.7 per cent to £3.56m in the period.