A company that oversees school bus transportation for the Kawartha-Pine Ridge District School Board and two other boards in Central Ontario has accidentally posted information about students online.

Student Transportation Services of Central Ontario says an internal staff training document was ``inadvertently'' shared on Facebook and Twitter, while posting an update regarding bus operator contract negotiations last week.

The company says the document included a link that allowed access to information about students, including their date of birth and address.

It says that it removed the PDF and closed off access to the database as soon as it learned of the issue.

But it says information about a small number of students was accessed, and those affected have been notified.

The company says it has ``put measures in place'' to prevent it from happening again, but did not provide details.