The Department of Health on Saturday said it had ordered the Union Hospital to hand in a report after hackers attacked its computer system.

Responding to media enquiries, the department said it was notified by the hospital on Monday about the cyberattack, which affected operations.

It said initial understandings showed that the incident did not involve patients' information or affect the safety of hospital services.

The authorities said the investigation is ongoing and it had ordered the hospital to submit a detailed report within a month.

The hospital earlier said it had reported the case to the police as well as the Office of the Privacy Commissioner for Personal Data, and announced it had stepped up measures to prevent further attacks.

"The hospital has activated an emergency response system and stepped up cybersecurity measures to block further intrusion. A team of cyber security experts has been appointed to conduct a thorough system inspection and recovery in order to ensure medical service continuity," it wrote in a statement.