A gang of six men pleaded guilty to an attack that - but for a piece of good luck - would have resulted in large numbers of casualties.
They planned to bomb a town centre rally in Dewsbury - held by a far right group.
But by chance it ended early.
Also by chance they were pulled over on the way home.
ITV News correspondent Juliet Bremner has the details:
They had previously denied the charge but Jewel Uddin, 27, Omar Mohammed Khan, 31, Mohammed Hasseen, 24, Anzal Hussain, 24, Mohammed Saud, 22, and Zohaib Ahmed, 22, changed their pleas.
They will be sentenced on June 6 with Judge Nicholas Hilliard QC, the Recorder of Greenwich, warning them: "This will attract significant custody. There is no doubt about that."
The murderous plan targeting the English Defence League (EDL) fell apart because the gathering in Dewsbury, West Yorkshire, finished earlier than expected.