With dangerously high levels of air pollution prompting the authorities in Beijing to order factories to halt their operations, experts have warned that the high air-pollution levels and the emergency responses being taken to tackle the problem can have an adverse effect on the Chinese economy and tourism.

The warning by the specialists came in the wake of the fact that the authorities in Beijing - which recently had acrid smog blanketing it - said on Monday statement that they had ordered the suspension of operations in 58 factories which reportedly have high emissions.

Talking about the move at a news conference on Monday, Li Hong - deputy director of Beijing's Economy and Information Technology Commission - said that the factories which had been ordered to halt operations included two cement factories, as well as factories involved in chemicals, metallurgy and building materials.

In addition, the authorities also ordered work to be halted at construction sites which could cause dust, like leveling land; following a similar move in Shijiazhuang, in neighboring Hebei province, where the authorities halted work at over 700 construction sites.

About the `air-pollution control' measures being taken in Beijing, Zhang Dawei - chief of Beijing's environmental protection monitoring center - said that air quality in the city witnessed a dramatic drop on Thursday and steadily worsened over the weekend; and added: "Beijing is a huge city with a lot of heavy industry. Under certain atmospheric conditions, the pollution is trapped.''