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April 10 (Reuters) - Canada's Garda World Security said on Wednesday it was in preliminary stages of considering an approach to the board of British rival G4S Plc for a possible cash offer to buy the company.
Garda World has until May 8 to announce a firm intention to make an offer or walk away. G4S did not immediately respond to a request for comment.
Shares of the world's largest security company rose over 30 percent to 241.7 pence and was at the top of FTSE mid-cap index .
Reporting by Sangameswaran S in Bengaluru; Editing by Arun Koyyur