JEFFERSON CITY, Mo. (AP) — Missouri’s health department says it mailed more than 10,400 letters to notify people that there was a security breach of personal information.

According to a Friday release from the Health and Senior Services Department, the 2016 breach included names, dates of birth and in some cases social security numbers. The health department discovered the breach in August.

According to the agency, department officials have no reason to believe the personal information was viewed or used by anyone intending harm.

Department Director Randall Williams says that a former state contractor might have illegally retained the information.

Office of Administration spokeswoman Brittany Ruess says the agency referred the issue to the Attorney General’s Office. She says the issue was not caused by a breach of the state of Missouri’s information technology system.