Arsenal signs French defender Koscielny

London: Arsenal has signed French central defender Laurent Koscielny from Lorient.

The English Premier League club said on Wednesday that the 24-year-old Koscielny signed a "long-term contract." Financial details weren't disclosed, but reports said the deal was worth 10 million pounds ($15 million).

Manager Arsene Wenger says Koscielny "has made big progress very quickly. He has shown he is mentally strong, he's a fighter and a very strong competitor."

Arsenal is in need of cover in defense with Sol Campbell still mulling over a new one-year deal.