Aviation safety campaigners in the United States say they have evidence a plane that crashed in India last year had previously suffered a series of technical failures, including a fire.
The Boeing 787 Dreamliner crashed on 12 June, shortly after taking off from Ahmedabad en route to London, killing 260 people.
The Foundation for Aviation Safety, a US campaign group, has sent a report to the US Senate outlining its findings, which it says are based on documents that have come into its possession.
The official investigation into the accident is ongoing. However, an interim report published in July sparked widespread speculation and controversy. Boeing declined to comment.
The aircraft involved in the accident, registered as VT-ANB, was one of the earliest 787s to be built. It first flew in late 2013, and entered service with Air India in early 2014.
