Williams was 44-years-old. He retired due injury at the end of the 1994-1995 season, although he later made an appearance for the club in a WRU Challenge Trophy match against Georgia in 1999. He is survived by his wife Gwen and their two daughters.
Neath Chairman, Geraint Hawkes said, "This is a sad day for Neath Rugby and for Welsh rugby as a whole. Brian was one of our great players and he was a genuine character. He attended a former players' reunion at the club only last weekend where, as ever, he was on great form. Brian was one of Neath's great players and his untimely death will leave a huge void at the club."
Head Coach Rowland Phillips commented, "To have lost Brian is an unbelievable shock. It is a huge loss for Neath Rugby and to Wales. The situation has still not sunk in and this is hard to accept but we send our sincere condolences to Gwen and the girls at this sad time."