Chicago police said in a statement that they have been in contact with the woman as well as Uber personnel, but declined to give further details.
Uber spokeswoman Jennifer Mullin called the incident “appalling and unacceptable.” She said the company immediately removed the driver from the Uber platform when it learned of the incident, and is cooperating with police in the investigation.
Mullin said that all drivers with the ridesharing service undergo a “rigorous background check.”
Uber is one of several ride-sharing services gaining popularity in cities, despite opposition from taxi companies that typically operate under stricter regulations.
The Chicago investigation comes as Uber has been in the news for other issues with government authorities.