LHASA -- More than 24,300 km of roads were constructed in southwest China's Tibet Autonomous Region from 2012 to 2017, according to local authorities.

At the end of 2017, the total length of sealed roads in Tibet stood at 89,504 km, with an average annual increase of 4,861 km, the regional transportation department said.

Tibet launched 3,005 rural road construction projects, with 1,325 completed, during the period, bringing the total length of sealed roads in rural areas to 60,000 km.

The region has spent more than 146.3 billion yuan ($23 billion) in fixed-asset investment in transportation infrastructure over the past five years, an average annual growth of 47.3 percent.

In 2018, it plans to invest 68 billion yuan in transportation.