Smog is seen over the city against sky during a haze day in Tianjin, China, January 2, 2017. REUTERS/Stringer

BEIJING (Reuters) - China’s smog-prone port city of Tianjin issued its first level 2 “orange” pollution alert this year effective from March 1, the city government said in a statement on its website on Wednesday.

Pollution is expected to blanket the city and nearby regions, including Beijing and Hebei, until March 4. No time was given for the alert to be lifted.

Emergency measures will be enforced on transportation and at industrial plants.

China has four levels of pollution alerts, graded from red to blue.