Why China is standing by Nicolas Maduro

China is Venezuela’s biggest creditor, has invested heavily in its oil industry and regards President Maduro as its strongest ally in South America.

China‘s leaders have reason to be especially concerned about the turmoil in Venezuela.

It is regarded as China’s staunchest ally in South America – a friendship that has been underpinned by huge loans, investments and weapons sales.

Al Jazeera’s Adrian Brown reports from Beijing.