Apple has launched an investigation into the death of a 23-year-old Chinese woman who was reportedly electrocuted while charging her iPhone 5.

According to Xinhua, the device was supposedly charging when its owner, a former flight attendant with China Southern Airlines, attempted to answer a call and was killed by high voltage.

On Sunday, the state-owned news agency Xinhua reported that Ma Ailun from Xinjiang autonomous region in China was found dead at her home after she took a call on her iPhone. Local police confirmed that Ma died of electrocution, but have not yet verified whether a smartphone (or its charger) was responsible.

Ma’s family has said it suspects that the woman was killed by the device “designed in California”, with her sister urging iPhone owners to be extra careful around their smartphones when they are charging.

The news of the incident has spread through Chinese social networks, with thousands of Internet users sharing the unconfirmed statement. Experts have suggested that any serious electric shock must have come from the charger not the phone - and the charger could only output lethal voltage levels if it was damaged.

“We are deeply saddened to learn of this tragic incident and offer our condolences to the Ma family. We will fully investigate and cooperate with authorities in this matter,” said Apple in an email to the media.

The Chinese police forces continue to investigate the case.