Marc, 28, joined West Ham United from RC Lens in January 1999 for a then Club record fee of £4.5million. He went on to make 48 senior appearances for the Hammers before moving to Olympique Lyon for £6million in May 2000.
Although he was only at the Club for little over a year, Marc quickly became a firm favourite with the fans and players because of his commitment on the field and his warm, friendly personality off the park.
Managing Director Paul Aldridge said: "I was devastated when I heard the news of Marc's death. He was very popular with everyone at the Club, a big man in every sense of the word. This is a tragedy for Marc's young family and our deepest sympathy is extended to them."
Chairman Terence Brown said: "I am deeply saddened by the death of Marc. He did very well for West Ham United during his short time with the Club and was highly regarded by everyone. A genuinely committed professional who will be a great loss to the football world."
If you wish to send in your condolences for Marc's family, we have opened up an online condolence book for your use. All messages will be passed on to his family.
Click here to send your message.