A 16-year-old might face jail after he confessed on Facebook to flooding Portsmouth's public library.
According to news reports, he blocked all the water passages in a restroom using toilet rolls and switched on the taps, which caused flooding to take place.
The flood in the library caused £150,000 worth of damage.
The teenager denied committing the act, but retracted his statement when the prosecutor found that he had admitted to doing it on the social networking site.
He was asked on Facebook if he was guilty, and had admitted to doing so. He had written: "Kind of, yeah. I've kept it to myself. A few mates know."
The library was shut for five months.
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