Malaysia has beefed up security ahead of a threatened hacking attack of its official government website by internet vigilante group Anonymous for government acts of censorship and will track down the activists, the police chief said on Wednesday.

In an attack codenamed Operation Malaysia, Anonymous said it would target the Malaysian government's online portal from Wednesday 1930 GMT to teach the country a lesson for censoring whistle-blower site Wikileaks.

We have received word of this threat. There are many agencies involved in this and we will get to the bottom of this, Malaysian police chief Ismail Omar told Reuters.

Investigation needs to be done and we need to protect our systems at the same time.

The Southeast Asian country could be the latest in a cyber-war waged by the activists, who gained prominence when they temporarily crippled the websites of MasterCard and Paypal that cut off financial services to Wikileaks.

The loosely affiliated hacking group has also attacked websites in Syria, Tunisia, Egypt and India.

In another posting on pastebin.com, Anonymous said Malaysia's censorship of films and television shows and its blocking of file-sharing websites amounted to a denial of basic human rights.

The Internet is here for freedom, without fear of government interference, the group said in a posting. We fear that if you make further decisions to take away human freedom. We are obligated to act fast and have no mercy.

In 2009, Malaysia planned to set up an Internet filter, similar to China's Green Dam project. But like the project in China, authorities quickly backed down following an outcry from the opposition and foreign investors.

A vibrant Internet culture has contributed to political challenges facing the Malaysian government, which tightly controls mainstream media and has used sedition laws and imprisonment without trial to prosecute bloggers.

(Reporting by Niluksi Koswanage; Editing by Ron Popeski)