Boeing Dreamliner: Battery probe results 'weeks away'

A US regulator has said it may take "weeks" for it to complete an investigation into battery problems in some of Boeing's 787 Dreamliner planes.

All 50 of the 787s in use were grounded until the investigation is completed, but the National Transportation Safety Board says the battery being used may not necessarily be unsafe.

They say overheating is to blame, but they are not sure exactly where the fault lies.

Jeremy Howell reports.