Reports of crime connected to online dating in Shropshire, Herefordshire and Worcestershire have increased five-fold in the past six years, new figures show.
Allegations have been made to West Mercia Police of crimes including blackmail, rape, fraud and stalking.
West Mercia Police recorded 56 alleged offences last year in connection with online dating, compared to 11 in 2011.
Among the websites listed in connection with the alleged crimes were Plenty of Fish, Badoo, Tagged, Lovoo and Ashley Madison.
The statistics show there were also 18 reported offences connected to dating apps Tinder and Grindr in 2016, compared to five in 2015.
Alleged offences included rape, harassment, distributing indecent photographs of a child and sexual assault.
West Mercia Police say the rise in reported offences is partly due to the increasing popularity of chat rooms, websites and dating apps.
People are being warned to be on their guard and never to disclose bank or credit card details.
Detective Sergeant Jon Cooper, of West Mercia Police’s economic crime unit, said: “West Mercia Police takes all such reports seriously and we work together with other agencies to robustly investigate offences and continue to protect our communities from harm.
“There has been a rise in the number of recorded crimes over the past five years, but this is in part due to the increasing popularity of chat rooms, websites and dating apps.
“While these approaches can prove successful for some, every year we investigate cases where unsuspecting people have become a victim after either meeting someone online or through apps.
“This can be hugely damaging for them – both financially and emotionally and although not everyone you speak to will be a fraudster, there are always people out there looking to exploit your trust.”
He warned people to be aware of being asked for “money transfers” and not to fall for elaborate sob stories.
DS Cooper added: “Always try to be open about any new relationship – tell a friend about your conversations and any plans to meet up with someone new in case they spot any red flags you may have not noticed.
“If you do meet in person, be aware and think about your safety.
“Stay in a public place, always tell someone where you are going, keep your phone with you, don’t leave your possessions or drinks unattended and do not drink too much.”
Last year, in relation to incidents with a connection to online dating, West Mercia Police investigated six alleged offences of assault causing actual bodily harm, six of blackmail, 10 of harassment, four of rape and four of stalking.
The figures were released following a freedom of information request.
Anyone with concerns, or who believes they have been a victim of an online dating scam, is urge to call police on 101, or 999 in an emergency.