A senior Pakistani meteorologist says heavy smog loaded with pollutants has covered the city of Lahore and elsewhere, causing breathing problems and disrupting normal traffic.

Mohammad Hanif said Saturday that several cities in eastern Pakistan have been engulfed in haze since earlier this week. He said the smog has caused irritation in residents' eyes and an increase in respiratory-related health problems.

Doctors are advising residents to stay indoors and wear facemasks outside.