Walker joined The Football Association in 1982 from his position as Commander with the Metropolitan Police force where he gained expertise in public order matters.

With The FA he advised the national team and club sides on security and crowd control issues when travelling abroad, and was influential in helping restore English clubs back into European competition following the Heysel Stadium disaster in 1985.

He continued to provide clubs with his knowledge up to last season when he assisted Chelsea during their European campaign.

The Football Association would like to send its condolences to Les' wife and family.