A new Crimestoppers campaign has been launched warning of modern day slavery in the region.
It is warning of the signs to look out for in a bid to help identify victims.
The charity said modern day slaves are often immigrants who may be seen 'operating openly in public places' such as car washes, nail bars and in agriculture.
But Crimestoppers said slaves may show signs of injury, abuse and malnourishment, may look unkempt, have poor hygiene and may often wear the the same clothing.
They charity said they may appear to be under the control and influence of others and may live in cramped, dirty, overcrowded accommodation.
Slaves may be collected very early and returned late at night on a regular basis and may have no access or control of their passport or identity documents.
They may appear scared, untrusting and isolated.
Crimestoppers statistics show a 136 per cent increase in information received on slavery in the past six months compared to the previous six months.
Gemma Wilson, Crimestoppers' Regional Manager for Yorkshire and the Humber, said: “It’s so awful to hear that slavery is even an issue in this day and age, but we want to reassure victims that it is an issue that is taken extremely seriously, and make it clear to perpetrators that they will be found and prosecuted.
“By launching this campaign, we will educate the public as to the signs to spot and let them know that they can take action on this horrendous crime, without compromising their anonymity. They will never have to give a statement to police, or go to court. No-one will ever know where the information came from.”
Former South Yorkshire Police officer, Paul Broadbent, now chief executive of the Gangmasters Licensing and Abuse Authority, said: “The public need to understand and be aware that modern slavery is happening right now, in and around the communities they live.
“Exploiting someone for their labour, forcing them to work, using people as commodities – these practices are abhorrent and we need the public’s help to stamp it out. Crimestoppers’ support will be invaluable in giving people the confidence to report their concerns.”
To pass on information to Crimestoppers, anonymously, call 0800 555 111 or visit www.crimestoppers-uk.org.