Short-term home rental company Airbnb said Monday it would invest in new technology to crack down on modern slavery, amid concerns that traffickers are turning its properties into "pop-up brothels" to sexually exploit vulnerable women and girls.

Airbnb exclusively told the Thomson Reuters Foundation that it has teamed up with anti-trafficking charity Polaris to train its employees, develop new systems and work with the police to spot signs of slavery and prevent people from being trafficked.

The U.S.-based company — valued at about $31 billion — is part of a growing drive to root out modern slavery from the hospitality sector, mainly involving the sexual exploitation of women and children.