China has urged the US and Canada to "clarify" the arrest of Meng Wanzhou, Huawei's chief financial officer. The daughter of the founder of the Chinese telecoms giant was arrested in Vancouver on 1 December and could face extradition to the US. Details of the arrest have not been released but the US has been investigating Huawei over possible violation of sanctions against Iran. China demanded her release, saying her detention was possibly a rights abuse.
Huawei is one of the largest telecommunications equipment and services providers in the world, recently passing Apple to become the second-biggest smartphone maker after Samsung.
Ms Meng has sought a publication ban on the details of the arrest, which has been granted by the courts. Huawei said it had little information about the charges and was "not aware of any wrongdoing by Ms Meng".
European shares hit a two-year low and indexes across Asia dropped sharply following the arrest.
A Chinese foreign ministry spokesperson told reporters: "The detention without giving any reason violates a person's human rights."
"We have made solemn representations to Canada and the US, demanding that both parties immediately clarify the reasons for the detention, and immediately release the detainee to protect the person's legal rights."
The focus of China's protest will likely astonish campaigners who have criticised Beijing's own record on rights issues. Amnesty International says there are "serious threats to human rights" in China and "anyone who speaks out against the authorities faces harassment, arrest and detention".