Osaka University said Wednesday that personal data of around 80,000 students, graduates, staff, former workers and others may have been stolen by hackers.

Data pertaining to about 69,000 people — which includes names, identification numbers and email addresses — may have been stolen. In addition, information included in personnel emails regarding up to 11,000 people was possibly breached due to unauthorized network access between May and July, the university said.

Using one lecturer's ID and password, the university's computer system was illegally accessed several times from overseas. A manager's ID was obtained through the access sessions, which in turn was used to install data-stealing malware, according to the university.

The stolen information also contained lists of donors to the university and pay records.

"We deeply apologize for causing great trouble," said Yoshihiro Kizawa, a university trustee.

The school said all computer system users changed their password as a countermeasure. No breach of patients' data at Osaka University Hospital has been confirmed.