The Bombay High Court on Tuesday expressed concern over the "deteriorating" air quality index (AQI) in Mumbai while taking suo motu (on its own) cognisance of the issue.

A division bench of Chief Justice D K Upadhyaya and Justice Arif Doctor sought a response from the Central and Maharashtra governments, Brihanmumbai Municipal Corporation, Maharashtra Pollution Control Board (MPCB) and Central Pollution Control Board (CPCB) on the matter.