London (CNN) An American Airlines flight from London to Philadelphia landed in Ireland after cleaning chemicals leaked in the aircraft cabin on Monday.

"American Airlines flight 729 from London Heathrow to Philadelphia diverted to Dublin due to an odor caused by a spilled cleaning solution in the galley," an American Airlines spokesperson said in a statement.

Katie Phillips, a passenger on board the diverted flight, tweeted that a "chemical spillage" led to a "sickness outbreak" on the plane.

Phillips told CNN the odor smelled, "slightly sweeter than fuel."

"We were delayed for nearly an hour at Heathrow when they suspected a strange smell," said Phillips, adding that the aircraft took off anyway.

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