The number of visitors was 20 per cent up on last year's opening day and sellers said book fans - some of them with suitcases to carry their purchases - had started queuing outside earlier than usual.

Chelly Fok, a 19-year-old Form Seven pupil, was the first in the queue. 'I am aiming at a limited edition of a fiction book,' she said.

One of the most popular books was Szeto's The Endless River Eastward Flows: A Memoir, Yuen Kwok-sum, of Greenfield Book Store, said.

More than 100 copies were sold in the afternoon alone. And many had their eyes on bargain books costing as little as HK$10 each.

'A man bought about 30 of the HK$10 books. It could be something to do with inflation,' Yuen said.

Buyers were also keen to get their hands on hugely discounted books, particularly on history and politics due to the centenary of the 1911 revolution, publishers said.

But Luck-Win Book Store manager Lam Pik-fun said sellers were still waiting for another blockbuster series like the Harry Potter books to boost profits in the coming years.

Some of the longest queues were at the stalls of fashion magazine publishers who handed out gifts to subscribers. Free cosmetics were a big draw for female readers.

Frequent fair-goer Lisa Hews and her daughter Cora Yau See-wai brought two suitcases with them and planned to spend more than HK$1,000, almost half the family's annual book budget.

'We wish we could bring bigger suitcases, but that may block the traffic,' joked Hews.

Pseudo-models may have been banned officially from signing autographs at the book fair.

But on the first day, they still managed to titillate some, and offend others.

Phoebe Hui, whose book of photographs was on sale, drew a huge crowd of mostly male fans when she made an appearance.

'This album seeks to convey the feeling of sex,' she said.

The book fair allows the sale of photo books of models in swimsuits, though critics argue such publications blur the line between literature and soft pornography.

The models are allowed to attend the fair but cannot sign autographs.

The signing ban was imposed last year after several pseudo-models kissed and hugged their fans as a marketing strategy.

Many visitors complained, saying such behaviour reflected badly on the event.

Some of the more well-known pseudo-models, such as Chrissie Chau Sau-na, were absent yesterday

Last year, Chau and a fellow pseudo-model skirted fair rules by holding autograph sessions at a tunnel near the adjacent Golden Bauhinia Square.

Benjamin Chau Kai-leung, deputy executive director of the Trade Development Council, said a foreign exhibitor removed books after it was warned about explicit content.

He said the organiser had received no complaints about the models, who were allowed to exercise freedom of speech and movement at the fair as long as they did not cause major disruption.

He advised them to be mindful of the fact that the event's visitors included children.

Meanwhile, one of the most popular events at the fair at the Convention and Exhibition Centre yesterday was a talk by Li Chengpeng, a mainland blogger who has more than three million followers.

More than 200 attended, drawn by his black humour.

He said his son had told him that instant noodles in Hong Kong tasted quite different from those on the mainland. He replied: 'Of course, they don't contain melamine.'