The 43-year-old man, surnamed Hu, works at a cement factory in Chongyang, Hubei province, according to Chutian Metropolis Daily.

But how the nail became lodged in his skull is a mystery to everyone, including Hu.

‘I have no idea why there is a nail in my head,’ he told the newspaper. ‘My job is to monitor the security surveillance cameras in the factory – it has nothing to do with nails.’

Hu said he had suffered from mild headaches last week and when the pain got worse on Friday he went to hospital, reports scmp.com.

After they did a CT scan, doctors at the Chongyang People’s Hospital were shocked to discover a nail hanging from the right side of the man’s skull, according to the report.

The doctors said Hu’s other health indicators such as blood pressure were all normal, and it was not clear how the nail ended up there.

Hu will now travel to a hospital in the provincial capital Wuhan for an operation to remove the nail.