A large tortoise on the track caused trains to come to a halt in southeastern England, a rail company informed frazzled travellers Monday.

Greater Anglia rail company tweeted that trains between the city of Norwich and Stansted Airport were stopped for more than an hour due to a "giant tortoise".

The operator first announced the line was blocked by "animals on the railway" early on Monday afternoon.

One passenger on a train to Norwich, Diane Akers, posted a photo of the tortoise standing on the track just after noon, reporting to the train company: "it's still alive but injured".

The tortoise's shell appeared to have a large gash on top.

"I couldn't believe my eyes to be honest!" Akers wrote.

A Greater Anglia customer adviser called Georgie later wrote that the tortoise was injured and had been taken to a specialist team for treatment.

"We have been informed that he will make a full recovery," the adviser updated.

One passenger, Lydia Jane White, tweeted: "'Train delayed because of a giant tortoise, too heavy to lift, stuck on the train tracks after having escaped from a local wildlife centre' is not something I thought I'd ever hear from a train driver!".

The railway line reopened around 1.5 hours later, while knock-on delays were predicted.

The bizarre delay came as UK passengers have experienced several days of train strikes this summer as railway employees' trade unions demand pay rises reflective of inflation.

am/gw