The Massachusetts Senate on Thursday unanimously approved a bill aimed at fighting human trafficking in illicit massage businesses across the state.

The  legislation would close a legal loophole that exempts businesses that claim to practice “bodywork therapy” from the licensing requirements that apply to massage parlors.

State officials have long struggled with a proliferation of illicit massage businesses, hampered by licensing regulations that carved out an exemption for those purporting to do “bodyworks” rather than massage.

Jo Gray, co-founder of Inman Oasis spa, said that bodywork encompasses a range of therapeutic practices, from energy-based Reiki to the more physical Shiatsu, and that these practices often require different levels of training from massage therapy.

A joint  investigation this year by the New England Center for Investigative Reporting and WGBH News found that hundreds of erotic massage centers in the state advertised on a Yelp-like website for buyers of commercial sex.

Massachusetts Attorney General Maura Healey praised lawmakers for passing the bill that she said would help authorities shut down illicit businesses that serve as a front for human trafficking.

“In case after case that we prosecute, human traffickers exploit the bodyworks loophole to oppress victims, escape oversight, and avoid law enforcement,” Healey said in a prepared statement. “This legislation will allow the state to shut down fronts and illicit actors, while helping to legitimize law-abiding healing practitioners.”

The bill was filed by Sen. Mark Montigny, a Democrat from New Bedford, in cooperation with the Office of the Attorney General and the state Division of Professional Licensure.

Audra Riding, Montigny’s general counsel, said the legislation is a “significant expansion” of an anti-sex trafficking bill passed in 2011. The bill also seeks to raise awareness about human trafficking by providing training for medical professionals and others who come in contact with victims of human trafficking, she said.

The bill would also allow for public and practitioner input on licensing requirements, to ensure that bodywork practitioners without the training to qualify for a massage therapy license don’t lose their ability to work.

“Many of these modalities have professional organizations with standards. We basically want to adopt the standards they’re already using,” Riding said. “We want to do everything we can not to place a burden on folks who are not doing anything wrong.”

The bill now heads to the House for consideration. Former iterations of this bill have passed the Senate several times with some variations, Riding said. Now she’s hopeful that, with the help of the law enforcement agencies and anti-trafficking advocates rallying behind it, the bill will move forward.

“We sense momentum building for sure,” she said. “It’s a problem we have to fix. These are people's lives.”

Read WGBH News' and NECIR's five-part series, "The Business of Illicit Massage."