Specialist police are at Heathrow Airport all week as part of a national crackdown raising awareness against forced marriages, female genital mutilation and modern slavery.
Last year, the Home Office supported victims in 1,764 suspected cases of forced marriage, 574 of which involved under-18s.
These cases were linked to 74 different countries, the most common of which involved travel to Pakistan (769 cases), Bangladesh (157 cases) and India (110 cases).
Officials say real numbers are likely to be much higher because the crime goes unreported.
Polly Harrar, founder of the Sharan Project charity, said forced marriage victims have been identified between the ages of two and 80.
Coercing or forcing children into marriage is illegal and can involve physical, sexual or emotional abuse. Sometimes children are, understandably, too frightened to speak up because they believe they have no control over the situation and they worry they will get their family into trouble or be disowned by their parents. But it's so vital that they do speak up. We want them to know that they can always talk to Childline, no matter the hour, and there is always a counsellor ready to listen and to help.
Watch the full report from Chloe Keedy below...
The Home Office say there's been a 47 per cent increase in the number of forced marriages they've seen since last year.
The summer is a key time when vulnerable people can be forced into dangerous situations. Chloe Keedy explains.
Interviewees: Richard Smart, Border Force; Det Sgt Trudy Gittins, West Midlands Police; Sabita Kaushal, Border Force; and Allen Davis, Metropolitan Police.