Immigration chiefs are considering moving high-risk sections from the department's Wan Chai headquarters, where an arson attack involving right-of-abode seekers injured 50 people last week. The move came as two major abode-seekers' groups prepared to meet tomorrow to calm emotions among 7,000 members and head off any further violence. Director of Immigration Ambrose Lee Siu-kwong said his department would review ways to strengthen security at Immigration Tower. His deputy, Choy Ping-tai, told three staff associations a committee chaired by an assistant director would study requests to arm guards with shields, batons and pepper foam. Chiu See-wai, chairman of the Immigration Service Officers Association, said the committee would give a report in a week's time when staff would be consulted again. Mr Lee said officers were studying legal and policy ramifications of equipping officers with weapons. Police have agreed to support the department if it needs equipment for temporary use. Mr Lee said: 'We'll conduct a detailed review to see how the overall security at the Immigration Tower can be strengthened. This will be more long-term. This will include a suggestion of removing some of the high-risk sections away from the building, such as whether the general investigation section which handles cases of illegal immigrants and overstayers can be moved from headquarters.' Security at Immigration Tower has been stepped up since the arson attack last Wednesday which injured 23 immigration officers. Seventeen of the injured remain in hospital. Five were in critical condition last night, including two immigration officers. Two abode-seekers' conditions deteriorated from stable to serious yesterday. Professor Peter Chan Siu-foon, a senior surgeon at Prince of Wales Hospital, which is taking care of three of the critically injured patients, said tomorrow would be crucial to their recovery. 'It's usually one week after the injury that you can tell more clearly the lung condition because the problem takes time to develop,' he said. Mr Lee said more than 30 officers had been counselled since the attack. Father Franco Mella, who has been helping the abode-seekers, is expected to attend tomorrow's meeting of the two abode-seekers' groups. Father Mella has been on the mainland. Fu Ka-wai, a representative of the Right of Abode Committee, said: 'We'll ask them to vent their feelings. We'll talk with them in the hope of minimising the chances of anyone who has radical thoughts doing something harmful to others,' she said. More than 1,000 officers from the seven law enforcement departments are expected to join a well-wishing gathering for the injured immigration officers on Thursday night.