In 1975 Hausner was handpicked by Siegfried Haag to lead the group, known as Kommando Holger Meins who conducted the West German Embassy siege in Stockholm to force the release of 26 of his RAF comrades.
While fellow Kommando Holger Meins member Ulrich Wessel was killed instantly (the explosion causing him to drop a hand grenade), Hausner was severely wounded in the explosion, with burns to over 40% of his body and a fractured skull.