Train services had to be stopped to rescue an injured giant tortoise that had strayed on to the tracks.
Clyde the tortoise was spotted walking the rail line to the disbelief of railway workers.
The pet was seen north east of Thetford, Norfolk, on the Cambridge-bound line at just after midday yesterday (1/8).
Four rail lines were affected – with two trains being terminated early and another starting 20 minutes behind schedule.
The 2.5ft (76cm) lumbering giant was spotted by a passenger on the 11:22 train from Ely to Norwich, who raised the alarm.
She told the BBC: “I tried to tweet Greater Anglia, but I’m not sure the message got through.
“When we got to Norwich station I told staff in the office there, and the chap looked at me as if I was mad – and then a police officer came along and said he’d seen my tweet.”
A Greater Anglia spokeswoman said: “We are sorry for the disruption caused to customers between Norwich and Cambridge this afternoon.
“This was due to a very large, injured tortoise on the line near Harling Road.
“Network Rail attended and helped the animal. Services were able to run from 13.25.”
The incident amused many on twitter, with one user posting: “The tortoise does his bit to support the rail strikes.
”Unfortunately he’s a bit slow.”
Clyde had gone missing on Sunday and has now been taken to a vets.