So-called honour-based violence and forced marriage offences are increasingly being perpetrated online, police and prosecutors have warned.
The trend was highlighted as the Crown Prosecution Service (CPS) and National Police Chiefs' Council (NPCC) emphasised their commitment to successfully investigate the crimes.
They have published a joint protocol setting out the principles governing the investigation and prosecution of offences in the categories.
Jenny Hopkins, Chief Crown Prosecutor for CPS East of England and lead on violence against women and girls, said: "This protocol emphasises how important it is for the police and CPS to work together closely, from the outset, to build the strongest possible cases. These cases are complex and the safety of the victim is vital.
"So-called honour-based violence/abuse and forced marriage is increasingly being committed online, usually by victims' families, extended families and communities.
"We know that offenders follow a course of conduct which is used to control, coerce, dominate or exploit a victim.
"It is important for police and prosecutors to remember that these cases may involve some of our most vulnerable victims and witnesses who may have the least confidence in the criminal justice process.
"In improving the criminal justice response to these crimes, this protocol is a key step."
The document highlights that a number of offences can be committed in the context of honour-based violence/abuse and forced marriage, including common assault, GBH, harassment, kidnap, rape, threats to kill and murder.
A victim's family or members of their community may go to great lengths to discover their whereabouts once a crime has been reported, the protocol warns.
It says: "The risks to the victim from her/his entire family, the offender's family and the community should be considered in such cases; not just the direct risk of the immediate perpetrator(s) on the victim. There is evidence that the risks to the victim increase after they have engaged with the police service."
In 2015/16 the volume of forced marriage referrals from police (90), cases charged (57) and prosecuted (53) were the highest on record, while three fifths (60.4%) of prosecutions were successful.
However, there were no successful prosecutions under a specific forced marriage offence, which was introduced in 2014.
Referrals of honour-based violence-related offences fell year-on-year to 216, with 182 defendants prosecuted and 91 convicted.
Commander Mak Chishty, NPCC lead for honour-based abuse, forced marriage and female genital mutilation, said: "So-called honour based violence/abuse and forced marriage are distressing and complex crime types which blight, and in some cases take, lives.
"Often the victim will feel unable to speak out about the abuse they are experiencing and will suffer in silence.
"The police service and CPS have an equal role to play in supporting victims and witnesses of these harmful practices whilst bringing offenders to justice. Our focus remains on putting victims, their safety and well-being at the heart of our investigations."
Copyright (c) Press Association Ltd. 2016, All Rights Reserved. Picture (c) Phillip Toscano / PA Wire.