Vehicles move on a road in dense fog in Lahore, east Pakistan, Jan. 24, 2019. Lahore and its surrounding areas were completely blanketed by dense fog on Thursday, minimizing visibility and disturbing flight, train and bus schedules. (Xinhua/Jamil Ahmed)

Laborers ride on a horse cart in dense fog in Lahore, east Pakistan, Jan. 24, 2019. Lahore and its surrounding areas were completely blanketed by dense fog on Thursday, minimizing visibility and disturbing flight, train and bus schedules. (Xinhua/Jamil Ahmed)

Laborers ride on a horse cart in dense fog in Lahore, east Pakistan, Jan. 24, 2019. Lahore and its surrounding areas were completely blanketed by dense fog on Thursday, minimizing visibility and disturbing flight, train and bus schedules. (Xinhua/Jamil Ahmed)

Vehicles move on a road in dense fog in Lahore, east Pakistan, Jan. 24, 2019. Lahore and its surrounding areas were completely blanketed by dense fog on Thursday, minimizing visibility and disturbing flight, train and bus schedules. (Xinhua/Jamil Ahmed)

Vehicles move on a road in dense fog in Lahore, east Pakistan, Jan. 24, 2019. Lahore and its surrounding areas were completely blanketed by dense fog on Thursday, minimizing visibility and disturbing flight, train and bus schedules. (Xinhua/Jamil Ahmed)