Officials in China this week examined the anuses of 10,000 pigeons that were set to be released today in celebration of National Day, amid government fears of a possible terrorist attack. According to reports from state-run media outlets, the birds had their feathers, legs, and anuses searched for "suspicious objects" yesterday, before being packed onto a truck and sent to Tiananmen Square in Beijing for today's ceremony. Many reports on the probe disappeared from China's tightly-controlled media after being published, though some articles and tweets remain online. The entire process was reportedly videotaped.

10,000 pigeons go through anal security check for suspicious objects Tue, ready to be released on National Day on Wed pic.twitter.com/HitEpLMv8o — People's Daily,China (@PDChina) September 30, 2014

The reports did not clarify what "suspicious objects" the inspectors were looking for, but security concerns are high following a spate of attacks that Beijing has blamed on separatist groups. The Uighurs, a Muslim minority in the western province of Xinjiang, have long sought greater autonomy from China, which has in turn stepped up its efforts to combat militants with raids and judicial crackdowns. Last week, the country jailed a Uighur advocate to life in prison for "inciting separatism." Violence has escalated in recent months, as well. Last year, an SUV drove into a crowd and burst into flames, killing five people; in March, 29 people were killed by a group of attackers in a Beijing train station. Officials blamed both attacks on separatist groups.

A Trojan pigeon attack may sound far-fetched, but it's not impossible, according to pigeon experts. "I have not heard of pigeons released at National Day requiring security checks, but it is possible for them to carry things such as explosives," a representative from the pigeon fan site China Pigeon Net told the New York Times. "They could carry something on their legs, under a wing, or in their anus."

The country is ramping up security ahead of today's celebrations, though some critics of China's sprawling government say the pigeon probe hits a little too close to home.

"The liberty and dignity of citizens are increasingly vulnerable, and can be expropriated at any time, like with the pigeons," columnist Zhang Ping wrote in an editorial. "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."