If you're in danger and you're frightened to speak, police can still help you.

That's the message of a new campaign which aims to inform people about the little-known 'silent solution' system.

All 999 calls are directed to centres and answered by operators. If no service is requested but something suspicious is heard on the line, the operator will put the call through to police.

Operators may ask callers to cough or tap phone keys in response to questions. However, if making a sound would put the caller or someone else is danger, calls are transferred through the silent solution system.

Callers will hear a 20-second automated message.

They will then be asked to press 55 to be put through to police call management. If a caller presses 55, police will be notified. If 55 is not pressed, the call is terminated.

Call handlers will be then attempt to communicate by asking simple 'yes' or 'no' questions.

The 'make yourself heard' campaign is being launched by the Independent Office for Police Conduct during National Stalking Awareness Week, which runs until April 12. It is supported by the family of murder victim Kerry Power, Women's Aid and Welsh Women's Aid, and the National Police Chiefs' Council.

Ms Power made her silent 999 call in the early hours of December 14 2013 when her ex-partner and stalker broke into her home.

She did not respond to the BT operator's instructions and her call was transferred to the silent solution system.

As 55 was not pressed, the call was terminated and Devon and Cornwall Police were not notified of Kerry’s call.

Her ex-partner David Wilder called police later that morning to report he had fatally strangled her.