China is investigating FedEx Corp. on suspicion of illegally handling a package to Hong Kong containing knives that are controlled by law, the state-run Xinhua News Agency reported.

The knives have been confiscated by authorities, Xinhua said, without providing more details. The case follows the discovery of a gun in a package delivered by FedEx to a company in China, the news agency reported Aug. 18.

The latest package “was handled correctly via standard security protocol,” FedEx said in a statement Tuesday. It was sent by “a regular shipper” from the city of Guangzhou but wasn’t delivered, the carrier said. Instead, it was turned over to authorities according to established procedures.

“The package never left its origin city, was never delivered, and remains with the authorities,” FedEx said in an email.

FedEx has been under scrutiny in recent months after Huawei Technologies Co. said documents it asked to be shipped from Japan to China were diverted to the U.S. instead without authorization. In another incident, FedEx said it mistakenly rejected a package containing a Huawei phone being sent to the U.S. from the U.K., a claim China rebuffed.

China’s Blacklist

After those incidents, people familiar with the matter said in June that China was considering adding FedEx to a list of so-called unreliable entities that the country says damages the interests of domestic companies. At the time, Chinese authorities had almost completed the preparations needed to blacklist the U.S. company, the people said.

FedEx has now put itself in a very dangerous position, with the unreliable entities list in the process of being rolled out, China’s state-run Global Times said on Tuesday. The parcel’s destination of Hong Kong is very sensitive, the newspaper said, adding that anti-Chinese government protesters in the city have often armed themselves with knives.

FedEx delivers more than 15 million packages a day.