The Beijing Tibet motorway in China is grid-locked again, this time the traffic jam is over 120 kilometers long and involves more than 10,000 cars.

The traffic jam has occurred in the Inner-Mongolia region of China and authorities say it is due to ongoing road works to expand the capacity of the highway, one of the busiest in the country and the world.

The rapid economic growth of China, and especially Beijing, mean that the country’s infrastructure has been unable to match the increasing demand.

The majority of vehicles trapped in the jam are reportedly trucks loaded with Beijing-bound goods, such as coal trucks delivering coal to the city’s voracious power plants.

The grid-lock comes just a week after a major traffic jam was cleared on the same highway after several days of bumper-to-bumper traffic.

China has experienced economic growth unmatched in the modern world in recent decades and is reportedly spending billions on expanding its road infrastructure.