Trains between Norwich and Diss were delayed after a swan was found on the track.
Greater Anglia said some lines were blocked on Tuesday night as a result.
In a Tweet just after 8.30pm the company said: 'Due to a swan on the track between #Norwich and Diss some lines are blocked. This is delaying trains between Norwich and Cambridge / Liverpool Street.'
Greater Anglia later said the disruption to services caused by the swan on the track had ended.
'For all those interested in the welfare of the swan on the tracks, it was safely rescued and currently in the cab with the driver until it can be released in a safe area,' the company Tweeted.
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