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 of about 69,000 people such as identification numbers, names and email addresses possibly have been stolen while information on about 11,000 people included in emails of school personnel may have been breached due to unauthorized access of its computer systems between May and July, the university said.

Using one lecturer's ID and password, the university's computer system was unlawfully accessed from overseas several times. It is believed malware was installed to steal data with a manager's ID taken through the cyberattacks, according to the university.

Lists of donors to the university and personnel pay records were also among the stolen information.

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

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