China allegedly directed an increase in cyber attacks on Australian companies this year that breached a bilateral agreement between the two countries pledging not to steal each other's commercial secrets, the Sydney Morning Herald reported Tuesday.

An investigation by Australian broadcaster Nine News and Fairfax Media — which owns the Sydney Morning Herald — found that China's Ministry of State Security was responsible for the so-called "Operation Cloud Hopper." It was a wave of attacks that were detected by Australia and its partners in the "Five Eyes" intelligence sharing alliance — which is made up of the U.S., U.K., New Zealand and Canada.

A senior Australian government source told the Sydney Morning Herald that China's activity was a "constant, significant effort" to steal intellectual property. Others said local companies and universities were not doing enough to tighten their cybersecurity against such attacks, the newspaper reported.

Cybersecurity experts also told the newspaper they had noticed "a significant increase in attacks in the first six months of this year" and that the activity was "mainly from China."

Relevant contact details for China's Ministry of State Security were not immediately available.

China's Foreign Ministry spokesperson Geng Shuang addressed the report during his regular press conference on Tuesday and said that cyber attacks are a common challenge faced by all countries.

"Relevant reports and accusations are fabricated without facts but with hidden motives," he said. "They are unprofessional and irresponsible. They will only heighten tension and rivalry, instead of helping to protect the common security of cyberspace."

The Sydney Morning Herald's report came after recent remarks from U.S. Vice President , who accused Beijing of intellectual property theft during the Asia Pacific Economic Cooperation Summit.

Western countries have long accused China of stealing intellectual property as well as commercial and military secrets, which Beijing has denied. In recent years, China has stepped up efforts to create sophisticated home-grown technologies as it aims to catch up with other high-tech countries like the U.S. and Germany.