Now repeat after me:
Its only a story...
Its only a story...
Its only a story...
Its only a story...
Quoted from Wikipedia, Criminal Damage Act 1971, original text can be found at http://en.wikipedia.org/wiki/Criminal_Damage_Act_1971
Section 1(1) provides:
A person who without lawful excuse destroys or damages any property belonging to another intending to destroy or damage any such property or being reckless whether any such property would be destroyed or damaged shall be guilty of an offence.
Section 1(2) provides:
A person who without lawful excuse destroys or damages any property, whether belonging to himself or another,
(a) intending to destroy or damage any property or being reckless whether any property would be destroyed or damaged; and
(b) intending by the destruction or damage to endanger the life of another or being reckless whether the life of another would be thereby endangered;
shall be guilty of an offence.
Section 1(3) provides:
An offence committed under this section by destroying or damaging property by fire shall be charged as arson.
The first offence is the all-purpose general offence whereas s1(2) the aggravated form because, unlike s1(1), it requires proof of a specific intent at the time the actus reus is committed (see concurrence), that life be endangered or there is an obvious risk that life will be endangered. Lord Taylor CJ. in Webster v Warwick [1995] 2 All ER 168 held that whether life was in fact endangered was irrelevant. The test was how was it intended or risked that life would be endangered. Thus, if the defendant drops a large stone from a motorway bridge intending to break the windscreen of a passing car, he or she may be convicted if the jury finds that there was an intent to shower the driver or passengers with broken glass and that, as a result, control could be lost, thereby endangering life.
Thus, you would be charged for arson.