Sadly, Björn Källberg passed away on 13 April 2001 at the age of 53. John Barnes, the chairman of Ada Europe, wrote the following after Björn's death.
Björn Källberg has been enthusiastically involved with the Ada programming language since it was first defined around twenty years ago. He became head of the Swedish delegation to the international standardization activities and made many important contributions to the various debates. He was elected a member of the Ada-Europe Board in1994 and was Treasurer since 1996. He was a very valuable member of the board and an excellent Treasurer. It was always a pleasure to work with Björn and he will be much missed by his many friends and colleagues among the international Ada community.