BANGKOK — The authorities were scrambling Monday to respond to worsening smog in the capital city.

A government spokesman said junta leader Prayuth Chan-ocha has ordered related agencies to inform people of the danger of ultrafine particles after Bangkok’s air quality this past weekend again fell to “unhealthy” levels.

As of Monday morning, the international Air Quality Index’s average ranking for the capital was 183, or “unhealthy,” though some areas such as Saphan Khwai and Lat Yao as of 10am were ranked at “hazardous” levels of 370 and 403, respectively.

Spokesman Puttipong Punnakanta said City Hall has instructed local offices to wash streets, spray water, get old vehicles off the road and regulate construction sites. He also said they would attempt to seed clouds to create rain in certain parts of Bangkok, which is not technically possible.

Asked about government plans to improve air quality while on a visit to Chiang Mai, Prayuth said the government alone cannot solve the smog problem because “everyone has contributed to” it.

Public frustration is mounting. The top five Thai hashtags on Twitter Monday morning related to smog: #Smog, #BangkokSmog, #PM25, #ToxicSmog and #SmogSmoke.

Air quality has suffered on and off in the capital for the past year, with the most recent downturn beginning late last month, when officials blamed it on weather conditions and vehicle emissions.

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