The Department for Agriculture, Environment and Rural Affairs (DAERA) has warned that Northern Ireland is experiencing high pollution levels in the northwest of the country.

The high levels of pollution are believed to be as a result of local pollution - home heating emissions and the current cold, calm weather conditions in which pollutants are not being dispersed.

DAERA said that during periods of high pollution the symptoms of people with lung or heart disease may worsen.

Healthy people are unlikely to experience any ill effects, it added.

The pollutants include sulphur dioxide, nitrogen dioxide, ozone and carbon monoxide.

The government has issued advice to the public to help reduce pollution:

When you have to drive:

Most people aren't affected by short-term peaks in air pollution. But some people with existing heart or lung conditions, may experience increased symptoms.

If you think you may be affected by air pollution levels, you should consider modifying your treatment when symptoms increase and speak to your doctor if this is not effective.