Security was so tight for China's National Day celebrations in Beijing that even the thousands of doves that were released during ceremonies had to undergo initimate anal security checks.

Worried that those symbols of peace could be abused as means of terror, Chinese security forces examined them for explosives before releasing into the skies of the capital.

Each one of the 10,000 birds had its feathers, legs and anus scrutinised to ensure they didn't conceal any suspicious material, state-run media reported.

"10,000 pigeons go through anal security check for suspicious objects Tue, ready to be released on National Day on Wed," The People's Daily newspaper tweeted in English.

The entire process was reportedly videotaped.

All the birds were eventually cleared of suspicion and released at sunrise in Beijing's symbolic of Tiananmen Square in a ceremony commemorating the 65th anniversary of the founding of the People's Republic of China.

The evening before, president Xi Jinping had addressed thousands of party officials at a high profile event also attended by his predecessor Hu Jintao at the Great Hall of the People, located in the iconic square.

News of the extra-cautious security measure triggering a wave of sarcasm on social media.

"The liberty and dignity of citizens are increasingly vulnerable, and can be expropriated at any time, like with the pigeons," Independent columnist Zhang Ping said in an editorial that was circulated on social media under his pen name, Changping.

"They have to go through the pains and insults of the rude anal check and yet they must appear peaceful and happy on the screen of the state broadcaster."

The pigeons' checks underscored Beijing jitters over possible attacks.

Tiananmen Square in particular is considered as a sensitive target since alleged separatist militants from the country's ethnic Uighur Muslim minority carried out a suicide attack that left six people dead there last year.