On Air Now
Heart Breakfast with Jamie & Lucy 6am - 9am
6 October 2010, 11:27 | Updated: 6 October 2010, 11:29
Commuters faced disruption this morning on the tube as some trains were removed from service because of suspected cracks on brackets.
Transport for London has started an investigation into the problem on 12 District line trains to find out if it's more widespread.
TFL has apologised to passengers for the disruption but say safety is their top priority.
It comes just two days after a strike by tube workers over job cuts caused travel chaos.