Image copyright Getty Images Image caption All the men were linked to a bookshop and publishers which sold books critical of China

Three Hong Kong booksellers being held in China will be released within days, say Hong Kong police.

Police in Guangdong said in a letter to the Hong Kong force that Lui Bo, Lam Wingkei and Cheung Jiping would be bailed pending investigations.

They have all appeared on state TV apparently confessing to smuggling illegal books into China.

It was unclear whether they would be able to return home and there was no comment on two other booksellers.

The three men, as well as Swedish national Gui Minhai and British national Lee Bo, are linked to a Hong Kong shop and publisher which sold books critical of mainland China.

The case has sparked international concern that China could be attempting to rein in freedom of expression in Hong Kong.

Their supporters believe they were abducted by China, though they have denied this.

Mighty Current publishing house disappearances

1. Lui Bo, General Manager, goes missing in Shenzhen, 15 October

2. Cheung Jiping, business manager, 32, goes missing in Dongguan, 15 October

3. Gui Minhai, co-owner, 51, goes missing in Thailand, 17 October

4. Lam Wingkei, manager, 60, last seen in Hong Kong, 23 October

5. Lee Bo, shareholder, 65, goes missing in Hong Kong, 30 December

The statement, reported by Hong Kong police, said Mr Lui, Mr Cheung and Mr Lam "were suspected to be involved in a case relating to a person surnamed Gui".

Mr Gui has also appeared on state TV, admitting to concealing books in his bag, and has been identified by the three as having been in charge of the operation.

Mr Lee, in another TV appearance, has denied allegations that he was abducted by China. He said he went to China voluntarily, but entered illegally, to help with the investigation.

Hong Kong police said they were continuing to investigate missing person cases filed on the three men to be freed, and were seeking further information from Guangdong.