Electric cars

One member of staff and a person from a partner company died in the crash.

The incident took place on Wednesday at about 17:20 local time, the firm said. The people who died were inside the vehicle as it fell from the building.

Nio says it immediately started an investigation into the incident in co-operation with government officials.

The third storey area from where the car fell has been variously described as a showroom, a testing facility or a car park.

 The car giants said they would work together to develop electric motors, transmissions and power electronics.

Both firms have struggled to maintain profit margins amid falling car sales and higher costs as well as the need to invest in future technologies.

Car firms are being forced to make low emission vehicles to meet more stringent anti-pollution rules.

There have been a number of similar tie-ups aimed at sharing the costs of developing electric cars.

The government's planned clean air zones are intended to encourage drivers to choose less-polluting electric cars.

Proposed for five English cities by 2020, the clean air zones will also introduce restrictions on older, polluting commercial vehicles.

But AA president Edmund King said drivers would be "baffled" by separate rules for electric cars.

Quality of life