A teenager suspected of hacking into the website of a seismological bureau in China and falsely warning of a massive earthquake has been caught by police, state media said on Monday.

The 19-year-old from east China's Jiangsu province, only identified by the surname Chen, admitted to illegally entering the website to show off his technical prowess, the state-run Beijing News reported.

Chen allegedly hacked into the website of Guangxi province's seismological bureau at the end of May, the report said, changing words on the home page to urge people to prepare for a "huge earthquake of magnitude 9 or more".

The earthquake that struck southwest Sichuan province on 12 May measured 8.0 on the Richter scale and left about 70 000 people dead or missing.

The deputy head of police in Nanning, the capital of Guangxi, alleged Chen also changed the news feed to assert that an expert had predicted the huge quake could soon take place in the province, according to the report.

Chen, an employee at a technology company, reportedly hacked into the website again on 1 and 2 June and deleted some data, according to the report.

Police caught Chen on 4 June in Taicang city, the report said, and found that the teenager had already been detained for five days in March for hacking into other websites.

There were no details as to when and if Chen would be tried, and local authorities contacted by AFP refused to comment.