Taipei: In response to US House Speaker Nancy Pelosi's visit to Taiwan, Chinese hackers planted the flag of China on the websites of several local government agencies across Taiwan.

While China's live-fire drills encircling Taiwan were taking place from Thursday, Chinese hackers covered a Kaohsiung government website with a China flag picture for over 10 hours from late Friday to Saturday morning, reported Taiwan News.

On Friday morning, it was admitted the website of Taiwan's Ministry of Foreign Affairs crashed for a few hours on Aug 2, 4, and 5.

The ministry explained there was a brute force attempt to crash the server, with up to 17 million times per minute access attempts from numerous Chinese and Russian IP addresses, reported Taiwan News.

As a result, central government agencies were told to stay on high alert for malicious internet activities.

People familiar with the matter told Taiwan News that central government agencies have been ordered to keep tabs on websites and report problems up the chain of command to the Cabinet, every hour from Friday to noon on Monday (August 8).

Emergency response guidelines issued by the Cabinet on Friday say a website has to be taken down immediately if it has been hacked.

Furthermore, the Ministry of Education informed schools nationwide of its own emergency response guidelines to ensure cybersecurity, in which 24-hour security monitoring of each school website and an hourly update is required until next Monday, reported Taiwan News.

As the tensions in the Twan strait heightened soon with US House Speaker Nancy Pelosi's visit to Taiwan, China has been increasing its military activities.

Multiple Chinese planes and ships were detected around Taiwan Strait, simulating an attack on its main island, the Defence Ministry said on Saturday adding that some of them have crossed the median line.

According to the Ministry of National Defence, the armed forces responded to such a situation accordingly with surveillance systems, CAP aircraft, naval vessels and missile systems.

"Multiple PLA craft were detected around Taiwan Strait, some have crossed the median line. Possible simulated attack against HVA. #ROCArmedForces have utilized alert broadcast, aircraft in CAP, patrolling naval vessels, and land-based missile systems in response to this situation," Taiwan's Ministry of National Defence tweeted today.

Yesterday, Taiwan's Defence Ministry said that 68 Chinese military planes and 13 warships crossed over the median line to participate in drills.

Taiwan Premier Su Tseng-chang blasted what he called "the evil neighbour" after China encircled the self-ruled island with a series of huge military drills that were condemned by the United States and other Western allies.

China is holding threatening military exercises in six zones off Taiwan's coasts that it says will run through Sunday. Missiles have also been fired over Taiwan, defence officials told state media. The speaker is the highest-ranking US politician to visit Taiwan in 25 years.

China opposes the self-governing island having its own contacts with foreign governments, but its response to the Pelosi visit has been unusually vociferous.