Twenty-four people, including a government property services manager and 10 of his staff, have been arrested by anti-graft agents for alleged corruption in relation to government maintenance projects. The 11 officers from the Architectural Services Department (ASD) and an engineer of the Buildings Department allegedly received paid sex trips to China and Macau on a weekly basis. The manager was arrested last Friday after he and four people - a senior property services officer, a property services officer, a maintenance surveyor and a subcontractor of the ASD - returned from what allegedly was a paid sex trip to Macau. Their movements in Macau were monitored by officers of the Macau Commission Against Corruption, which the Independent Commission Against Corruption said had helped secure evidence, including how they were entertained in a nightclub near the Holiday Inn. The ICAC said the officers had only conducted cursory supervision of work carried out by 12 arrested ASD subcontractors. However, the ICAC said there were no safety implications as most of the projects involved marble linings for outer walls of buildings. ICAC officers began their investigations several months ago after a complaint that claimed a senior property services officer obtained maintenance work from ASD registered contractors for companies in which he had a financial interest, through a company allegedly operated by his wife. The officer and his wife were arrested on Friday. Investigations allegedly revealed the couple and the arrested structural engineer from the Buildings Department had been operating five companies to secure orders from subcontractors of ASD contractors at low cost. In a statement, the ICAC said that apart from awarding maintenance works to these companies, the subcontractors allegedly provided nightclub entertainment, free trips to the mainland and Macau, and prostitution services to the senior property services officer and his colleagues involved in the scam. Inquiries also indicated that the five companies associated with the senior property services officer used inferior material in carrying out one maintenance project and requested a registered supplier to issue a false certificate to guarantee the quality of the materials. The ICAC alleged the arrested engineer had accepted cash, free trips to Singapore, nightclub entertainment and the transfer of ownership of a secondhand car. It is believed the alleged advantages were for the engineer to turn a blind eye to substandard work on an ASD project at a school in Tuen Mun. All the 24 arrested on Friday, aged between 25 and 55, were released on ICAC bail.