(Updates throughout with United Airlines comment)
SYDNEY, Oct 4 (Reuters) - A United Airlines flight carrying 194 passengers and crew from Los Angeles landed without incident in Sydney early on Thursday after a mayday call caused by low fuel triggered a major emergency response in Australia's largest city.
"United flight 839 from Los Angeles to Sydney landed safely ... following a mechanical issue," Madhu Unnikrishnan, a spokesman for United Airlines, said in an emailed statement.
"The aircraft taxied to the gate and all customers disembarked normally," he said.
A spokeswoman for Air Services Australia said the Boeing 787 triggered a mayday call due to low fuel reserves.
"No passengers were at risk at any time," she said.
A spokesman for Sydney Airport declined to comment.
The New South Wales state police said in a statement a major emergency response was activated at Sydney airport after "a pilot reported a problem".
Some major roads around the airport were closed as a precaution at 6.36 a.m. local time (2036 GMT Wednesday). The plane landed safely and roads were re-opened three minutes later. (Reporting by Swati Pandey Editing by Paul Tait)