Tarsus Group acquired 50% of the AMB Group, a South-East Asian exhibition organiser, for $13m.The business-to-business media group bought half of the company from Andrew Siow and Richard Yew via joint venture vehicle AMB Tarsus Exhibitions.The acquisition follows Tarsus' strategy to strenghten its portfolio and growth in the region. It plans to build on its existing assets in Indonesia and introduce a number of its brands into AMBT's markets of Malaysia, Myanmar and Cambodia.Tarsus will pay $13m for the 50% stake, made up of $4.1m in cash, $4.1m to be paid in January 2016, and deferred payments linked to the performance of the business up to the end of 2017.The total consideration for the initial 50% is capped at $20 million, and the company added there is the option to buy the remaining 50% stake.Tarsus raised its bank facilities to £75m from £60m to provide "additional headroom".Managing director Douglas Emslie said: "AMBT is an excellent strategic acquisition and allows Tarsus to build scale in South East Asia with an entrepreneurial partner."Many of the ASEAN economies are growing strongly and the AMBT joint venture will offer us first-mover advantage in some key sectors in these exciting markets."Investec analysts said: "This looks strategically on message and complements Tarsus' 'quickening the pace strategy', with emerging SE Asia sales doubling in size and good opportunities to push replications harder into the region with strong/known management."The broker rates the stock at 'buy' with a 290p price target.Shares were up 1.52% to 213.2p on Monday at 10:25.