GUJRANWALA: A GDA team Wednesday launched a grand operation against illegal housing societies and demolished walls and sealed offices of six societies. Talking to reporters, GDA Deputy Director Enforcement Arshad Warriach said on the directives of higher authorities, GDA have started crackdown against illegal housing societies and sealed the offices of six societies including Golden City, Islam Town and Kamboh Colony and demolished surrounding walls for not having NOC from the GDA. He said the operation would continue for several days and no one would be allowed to sale the plots without obtaining NOC.