A review by the National Crime Agency (NCA) highlighted the rise while the overall levels of such offending has remained fairly stable since 2015.

During the same period the proportion of reports from girls aged 19 and under rose from 12% to 22%, with boys in this bracket increasing from 25% to 31%.

The NCA's Serious Crime Analysis Section (SCAS) reviewed data from 671 cases of sexual assault after a first face-to-face meeting following initial contact via an online dating website or app.

This review covering 1 April 2003 to 21 March 2021 updated the findings of a 2016 NCA report which examined 163 cases identified between April 2003 and July 2015.

It found the largest proportion of both male and female victims were still aged 20-29, accounting for 40% of cases.

The victims in 83% of the 671 cases were female and 17% were male.

Only offending on SCAS databases were analysed and the figures did not include unreported incidents or offences which police forces did not send to the NCA to be examined.

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Louise Vesely-Shore, principal analyst in the SCAS team, said: "Although there hasn't been an overall increase in these offences since our initial report in 2016, it is notable that this form of crime continued during the pandemic despite the substantial restrictions on people's lives.

"Anyone dating online should be aware of the potential dangers, so they can be better prepared and make the choices that are right for them.

"We want people to protect themselves when meeting someone in person for the first time, as well as deter would-be offenders from committing these types of crimes."

There was an overall reduction in all types of offences reported to SCAS during the pandemic, the NCA added, but incidents linked with online dating appeared less affected.

In the financial year 2020/21, SCAS reviewed nearly 10 times as many cases of internet dating sexual offences compared to bogus taxi driver sexual offences.

The NCA is working with academics from the University of Birmingham to further explore the impact of the pandemic on stranger sexual offending generally.