Officials have been accused of deliberately concealing data that about 30 per cent of mainland immigrants eligible to come to Hong Kong are unlikely to do so. It was disclosed yesterday that when Secretary for Security Regina Ip Lau Suk-yee told the Legislative Council last week that 1.67 million mainlanders could come to Hong Kong, she also had data indicating a substantial minority would not do so - but did not tell legislators. Migrants activist Ho Hei-wah, director of the Society for Community Organisation, said the Government was wrong to release the 'scare figure' of 1.67 million on its own. 'The whole survey is being manipulated by the Government,' he said. Legislator Cyd Ho Sau-lan of The Frontier said Mrs Ip's motives for withholding data were clear: 'It would be an anti-climax after the 1.67 million figure.' It is understood survey data indicates about 30 per cent of people with children on the mainland told researchers they would not try to bring them to the SAR. The data will be released to Legco this morning. However, Commissioner for Census and Statistics Frederick Ho Wing-huen said yesterday that full data had been given to the Security Bureau before Mrs Ip's Legco statement. Despite the survey showing many mainlanders might not come, Mrs Ip told Legco that all 1.67 million would have to be 'absorbed in Hong Kong' and would 'pose a very heavy, and even unbearable, burden to Hong Kong'. Even based on government data, factoring in willingness to come could slash migrant figures by 250,000 to 500,000. Mr Ho Hei-wah said he believed the real figure of those not wanting to bring their children to the SAR would be even higher. 'Very few fathers will admit to a stranger that they do not want their children to come. It is very embarrassing,' he said. 'I know an eligible person in Shanghai who enjoys a very high living standard and is not at all interested in coming.' Ms Ho said it was not surprising many did not want to bring their children. 'If a man has a mistress over the border, how can he ask his wife in Hong Kong to look after children born to this mistress?' she said. A Security Bureau spokesman said Mrs Ip's statement was intended 'to give Legco members the initial findings of the survey to make the debate more meaningful'. Mr Frederick Ho said data on migration intention was 'a kind of opinion survey' and should not be compared to hard statistics about the number of offspring. 'The figures released should be reliable enough as the basis for the Government to make an assessment of the situation,' he said. A South China Morning Post report yesterday that much survey data had been rejected as unreliable, has sparked a major row over the half-completed survey used to generate the 1.67 million figure. Despite concern, government officials have called a special Legco meeting this morning to outline in detail the schools, hospitals and homes which would be needed to cope with the migrants.