Image copyright Citizens Advice Image caption Christine says victims of scams need to speak up about their experiences

When two men knocked on Christine's door saying her gutters needed cleaning and roof tiles needed replacing she agreed, and handed them £520.

That was a mistake. "When they were finished one said he'd give me a certificate for a 10-year guarantee.

"But when he went to the van to get it, he just drove off. I looked at the gutters and I could still see the weeds."

The 70-year-old from Sussex never saw the cash again - she had been scammed.

"The worst part was that it didn't seem, or feel, like a scam. They looked professional and said they'd completed work on my neighbours' houses," Christine said.

Scams Awareness campaign

She's one of almost 20,000 victims of similar scams who complained to Citizens Advice last year, an increase of 8% from the previous year.

Many victims ended up much more out of pocket than Christine: fraudsters on average cheated people out of almost £3,000 through these types of scams.

Scams sent through the post hit people even more, with the average loss at £5,435.

"Tried-and-tested scams still pose a huge threat," warned Gillian Guy, chief executive of Citizens Advice, which along with Trading Standards has launched a Scams Awareness campaign.

"Even in this digital age where online scams are on the rise, scammers are continuing to use traditional routes to prey on people.

"Tactics like doorstep selling, sending unsolicited letters and cold calling give scammers the opportunity to build a relationship with their victim."

The campaign - which has the slogan "Stop, report, talk: Be #scamaware" - hopes to encourage people to talk about their experiences and look out for others.

"People need to speak up about this sort of thing," says Christine. "Had I known the warning signs of scams - like being asked to pay up front in cash - alarm bells would've rung and I'd have thought twice about handing over my money."

Scam victim?

If you're worried that someone you know has become victim to a scam, look out for the following. Are they:

Receiving more mail than usual?

Receiving unsolicited calls or spending more time on the phone?

Struggling with money or have they withdrawn large amounts of cash recently?

If you think someone you know is being scammed, take the following steps:

If you're worried about telephone scams look into installing a call blocker

Encourage them to tell their bank immediately if there is any suspicious activity or transactions from their account or credit cards

Report the scam to the Citizens Advice Consumer Service online or by phone on 03454 04 05 06. They will give you advice on what to do next and report the scam to Trading Standards

Report the scam to Action Fraud on 0300 123 2040

Tip of the iceberg

"We believe that the number of complaints about these scams is the tip of the iceberg - only 5% of scams are reported," warned Lord Toby Harris, chair of National Trading Standards.

He added that scams which do not take place online can cause significant harm emotionally as well as financially, particularly when people - often in vulnerable situations - are deceived and put under pressure in their own homes.

Research by Citizens Advice showed three out of five people reported being targeted by a scam in the past two years. Of those targeted, less than half said they told anyone about it.

"We must work together to combat fraudsters by being more open about scams and helping each other understand what to look for," said Gillian Guy.