Police are carrying out searches in the street, on the transport system, at public events and elsewhere in London. It's no good saying you took a knife out for your own protection - it's illegal to carry one and you will be arrested. You are then likely to be charged and appear before the courts. This will mean you get a criminal record.

The maximum prison sentence for carrying a knife is 4 years but if it is used in a crime or to injure someone, then the penalties are a lot worse.

• Offensive Weapons legislation

YOU PUT YOURSELF IN DANGER: Carrying a knife makes you more likely to be a victim of knife crime. If you don't take it with you, the knife won't be used.

CAUSE INJURY: There is no safe place to stab someone. Whilst you may think it is ok to stab someone in the arm or the leg, they could die as a result. The knife could also be turned against you.

FAMILY: How will your family feel if you are caught with a knife? Ashamed of you? Worried for you? What if your younger brother or sister thought it was ok to carry a knife because they've seen you doing it - what if something was to happen to them as a result? How guilty would you feel? If you were to use a knife, you could destroy not only your victim's life, but also that of their families, your family, and ultimately your own.

YOUR FRIENDS: If you are with your friends and one of them uses a knife against someone, and the victim was to die, then you too could be charged with murder, and sent to prison.

CRIMINAL RECORD: A criminal record will affect your job prospects and could prevent you from traveling abroad.