Global integrated facilities management company OCS has completed the acquisition of City Group Security, a south-east London-based nationwide security firm founded in 1993 and ranked among the UK's 30 largest security businesses, in a move that significantly expands its security capability and operational density across London and the South East.

Facilitate Magazine reported that the deal adds approximately 600 new colleagues to OCS and broadens its security services across logistics, local government, education and utilities.

City Group Security delivers static guarding, canine security, mobile patrols, keyholding and alarm response services. Its self-delivered canine security operation is a particular addition for OCS, bringing specialist expertise in-house and supporting future growth of the service for customers across its national estate.

Daniel Dickson, chief executive officer of OCS UK & Ireland, said City Group Security has built a strong reputation in the security market over more than three decades, supported by experienced colleagues and long-standing customer relationships, adding that bringing the business into OCS strengthens its security capability and complements the wider integrated facilities management offer delivered to customers nationwide.

Steven Moore, managing director of Security UK at OCS, said City Group Security adds scale and density to the security business, particularly across London and the South East, and brings specialist capability that customers value. Moore added that the self-delivered canine security operation is a meaningful addition, allowing OCS to grow that service under one team.

The acquisition follows OCS's earlier purchase of Top Security in Ireland in March 2026 and its agreement to acquire EMCOR UK, reflecting a sustained period of acquisition-led expansion across the group's UK and Ireland operations.

Read the full report on OCS's acquisition of City Group Security and its implications for UK FM security services.