Media playback is unsupported on your device Media caption A man who uses gay hook-up apps explains why he uses them to meet people

Dating apps "must take more responsibility" for protecting their users' safety on dates, the National Police Chiefs' Council (NPCC) has said.

It comes after Stephen Port was found guilty of murdering four men he had met through such apps and websites.

Chief Constable Jane Sawyers, police lead for LGBT issues, said apps should provide safety messages.

One app, Grindr, did not reply to a request for comment. Tinder said it took users' safety "very seriously".

Ms Sawyers told the BBC's Victoria Derbyshire programme that while apps had a role in "signposting people to the police" after potential crimes had occurred, "they could do more to prevent the offences in the first place".

She suggested apps could display messages such as: "Get to know the person, not the profile," when users enter them, warning of the many fake accounts that exist across the various sites.

Ms Sawyers admitted there was still a "stigma" surrounding the reporting of crimes stemming from gay dating apps.

But, she said: "There shouldn't be any concerns about gay people reporting things to police... we're not there to judge, what we're interested in is justice for the individual."

In the UK, the number of people reporting being raped on a first date with someone they met on a dating app increased six-fold between 2009 and 2014 to 184 cases a year, according to the National Crime Agency.

And in the first six months of 2016, the Metropolitan Police has received 187 crime reports linked to Tinder and gay dating app Grindr.

Image caption Chief Constable Jane Sawyers wants apps to display safety messages

'I was petrified'

Josh French, 24, uses dating apps on a daily basis.

During his first experience of Grindr, he was invited to the home of a man he had been in touch with on the app for a month.

When he arrived, he found the man and three friends high on drugs, and remembers being "petrified".

"It was really quite scary, he was really full on - had his hands all over me," he says.

"They just kept on offering me drugs."

Mr French was eventually able to leave the property, but admits he was "naive" in not telling anyone where he was going.

"I felt like anything could have happened," he says.

He did not report the incident to police.

Asked in what instances he would contact the authorities, he says "perhaps" following a rape or serious assault but adds: "Even then, there would be serious hesitation."

Mel Stray, from the LGBT charity Galop, said it had seen "a dramatic rise in the number of sexual offences reported to us".

She called for "better whistle-blowing facilities for people to report fake profiles, [to ensure] those profiles do get taken down".

But she was also critical of the lack of convictions made by police and the wider justice system when such incidents were reported.

"Of the over 100 cases we've seen in the last few years where clients have come to Galop and reported sexual assault in a chemsex or hook-up context, not one person has been charged or sent to court," she said.

Ms Sawyers said police officers were now receiving training on how to deal with such cases, adding: "These sorts of offences are more prevalent now than your traditional offences."

Tinder said in a statement: "We authenticate each user's identity using Facebook login.

"We take our users' safety very seriously and continuously advise our community of millions of users to be vigilant [and] report any suspicious activity."

How to stay safe when using dating apps

Meet in a public place you are familiar with - and know a nearby location if things go wrong

Tell a trusted friend or family member where you are going and who you are meeting

If you feel unsafe while out on a date, go to the bar and "ask for Angela" as a codeword for help

Don't let your guard down after the first date - keep telling friends and family where you are

Consider pairing up with a friend and go on separate dates in the same place

Have an "out" in case the date goes badly - such as an excuse of later plans like dinner with family

Sources: Victim Support and Ask for Angela

The Victoria Derbyshire programme is broadcast on weekdays between 09:00 and 11:00 on BBC Two and the BBC News channel.