"As confirmed on Tuesday night in Arsene Wenger's post-match press conference, Arsenal Football Club is delighted to announce that Alex Song has signed a new long-term contract with the club," the statement said.
Song, 22, has established himself as a first-team regular over the past year, three seasons after joining from French club Bastia in 2006.
The Cameroon international follows on from Croatian striker Eduardo and prospect Sanchez Watt, who both signed new long-term deals in the past week.
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