A United Airlines Boeing 787 Dreamliner bound for Tokyo has been forced to land in Seattle due to a technical issue.

United Airlines Boeing 787 Dreamliner
United Flight UA 139 (callsign UAL139) had been headed for Narita International Airport (NRT), Tokyo, Japan from Denver International (DEN) when the crew noticed a potential issue with an oil filter.
Aircraft UAL139
The aircraft landed at Seattle-Tacoma (SEA) just after 16:00 local time.The issue is likely to be a concern to Boeing following the fleet wide grounding of the entire 787 fleet earlier this year.
Airlines across the world were cleared to resume 787 flights only last month. The fact that this aircraft landed in Seattle, near to where the aircraft are built, will give Boeing the perfect opportunity to quickly investigate and resolve this issue.
Passengers were accommodated in Seattle overnight and are expected to resume their flight to Japan on Wednesday.
The aircraft involved in the incident (tail number N26906) is shown below:

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