Chinese Internet giant Baidu Inc is investigating how online searches for a doctrine espoused by President Xi Jinping led users to a video clip that appeared to poke fun at the policy, people familiar with the matter said.

The search engine, like all Internet companies in the country, typically censors content to eliminate politically sensitive topics. But on Tuesday afternoon, people who hunted on Baidu for Xi’s “Four Greats” – a policy doctrine attributed to the Chinese leader – found results that featured a video explaining the local phrase for “tooting one’s own horn”.

Baidu fixed the issue by the evening but is investigating how the two topics got correlated, the people said, requesting not to be named because the matter is private. From July 24, the same search called up links to various government and news websites.

The apparent glitch, which some users noticed and circulated on private social media, marked the latest embarrassment for China’s leading search engine. Beijing requires its largest online platforms to screen for words and images deemed inappropriate or critical of the Communist Party. Failure to do so can incense regulators, which can demand companies overhaul their operations, suspend services, pay fines or even shut down.

The Chinese Internet giant came under fire in 2016 when a university student died after trying out an unorthodox medical treatment found on Baidu.

Internet search technology remains far from perfect. Google itself briefly mis-translated for Asian users Chinese sentences relating to Hong Kong, igniting debate about its stance on protests in the city over a controversial extradition bill. Google said in a statement at the time that its translation service used the patterns of millions of existing translations, and that the automatic systems sometimes made unintentional mistakes. – Bloomberg