Claustrophobic Corinne Black was left feeling flushed when she became trapped for 20 minutes in a superloo.

Miss Black did not just spend a penny, she paid 20p to use the futuristic tin throne.

But to her dismay, when she pressed the green button to exit, the sliding door just would not budge.

Miss Black, who was returning from an art class with a friend when she found herself caught short, said: "I will never use one of those toilets again. I would rather wet myself."

Miss Black, 50, frantically stabbed at the red emergency button but to no avail.

She was hysterical by the time she managed to prise the door open with her fingers and escape from the toilet in West Drive, Brighton, on Thursday afternoon.

But for Miss Black, of Hereford Road, it is not the first time she had found herself trapped.

She used a superloo in Upper Rock Gardens 18 months ago and was stuck inside it for half an hour until her cries for help were heard by two men who forced the door open.

She said: "This was the first time I had used one since I first got trapped and it was only because I was desperate.

"I was in a terrible state. If you are claustrophobic it is horrific. I was hysterical because I knew it took half an hour to get out the last time.

"There was water coming down from the ceiling but the door briefly opened and I managed to grab it with my fingers."

Miss Black's friend had run to a nearby phonebox to call the police but before she could call Miss Black managed to free herself.

Miss Black said: "I shouted to my friend that I couldn't get out. I started panicking and said she would have to call the police.

"In the end I was so hysterical I was bashing the door and shouting, 'Get me out of here'."

Miss Black is calling for other people who have suffered the same experience to persuade Brighton and Hove City Council to investigate the door mechanisms to stop it happening again.

She said: "If I could get enough letters of complaint it might be enough to get them to change the mechanisms on the doors.

"Those toilets are a good idea but because they have made them so vandal-proof it is failing other people."

A spokeswoman for the city council said: "All our superloos are checked twice a week.

"We have had few complaints about people getting trapped so it's very unfortunate it has happened twice to this lady."