Nature Communications 3: Article number: 1135 (2012); Published: 16 October 2012; Updated: 16 December 2013.

The original version of this Article contained an error in the calculation of the force per fibre (σcrit) values in the fibre bundle model. During re-evaluation of the paper after publication, it was discovered that a step in the calculation of σcrit—multiplication by the proportion of remaining fibres to the initial fibres (U)—had been omitted, resulting in a small error in the final values of σcrit and in the final fragmentation threshold pressures throughout the paper including Table 1. For example, the fragmentation threshold pressures quoted in the Abstract required revision from ‘5–6 MPa’ to ‘9–10 MPa’. These changes have now been applied throughout the PDF and HTML versions of the Article.