May, writing in The Sunday Times, said she will introduce a "modern slavery" bill to help eradicate an "evil in our midst" six months after a major study concluded that political indifference and ignorance among police and social workers was helping foster a contemporary version of 19th century slavery in Britain.
The March study by the Center for Social Justice found that thousands of people were being used for forced criminality, such as benefit fraud, organized begging, forced pick-pocketing and drug cultivation.
Researchers also gathered evidence of exploitation of foreign adults and children, as well as British citizens, in factories, fields, construction sites and brothels, The Guardian reported.
May said her bill is aimed at coordinating efforts to combat modern slavery under Britain's new National Crime Agency and to elevate it to a top priority.
"It is scarcely believable that there is slavery in Britain, yet the harsh reality is that in 2013 there are people in this country forced to exist in appalling conditions and often against their will," she wrote.
"The criminals who exploit, bully and threaten them often inflict violence mercilessly. They are careful to ensure their victims have no rights. Those victims are, to all intents and purposes, slaves."
May said under her proposed legislation, new "trafficking prevention court orders," such as those currently used for sexual offences, would be introduced.
Also, a "modern slavery commissioner" position would be created to make sure police agencies are tacking the problem.
The Sunday Times, citing Whitehall sources, reported ministers are considering making the organization of slavery an "aggravated" criminal offense, with those convicted of using abduction, threats or extortion to control slaves facing sentences of up to 14 years.
"For too long modern slavery has been seen as someone else's problem," the home secretary wrote. "Some believe it is an illegal immigration problem, others that it should be tackled through victim support, but most importantly many don't see it for what it is.
"So let me tell you what I believe it to be. It is a horrendous crime, it has got to stop and it is everyone's problem."
The March study found that perceptions among police and other authorities about the nature of the modern slavery phenomenon were inaccurate -- most believed it mainly involved immigrants and that the victims almost exclusively women and girls.
But researchers found many cases of British girls being trafficked within the country, mainly for sexual exploitation. Meanwhile, most of those who were rescued weren't kept safe -- 60 percent of children placed in local custody later disappear because they so fear their abusers they take the first opportunity to go back, the Guardian reported.
"Our research has uncovered a shocking underworld in which children and adults, many of them U.K. citizens, have been forced into lives of utter degradation," Christian Guy, managing director of the Center for Social Justice, wrote in the report. "Yet the authorities are either failing to understand the nature of this abuse or turning a blind eye to its existence."