It happened in a ground floor toilet
A man has been arrested following a fire at Derriford Hospital in Plymouth.
Fire crews were called to the blaze in a ground floor toilet at around 6pm on Monday 10 April. The fire had already been put out before they arrived.
Following police enquiries, a man in his 20's from Plymouth was arrested on suspicion of arson with intent to endanger life.
He remains in police custody.