Sources said the court set up air pollution measuring devices on both sides of the road at Olonkar intersection and found 71 vehicles were seriously emitting black smoke.

The vehicles, including bus, truck, covered van and lorry, were emitting black smoke about 18% to 20% above the standard level of emission.

The court conducted by Chittagong Port Authority (CPA) Magistrate Muhammad Munir Chowdhury realised Tk 3 lakh from the vehicles under Environment Act and detained four trucks for lacking in fitness and having date-expired fitness certificates, said the sources.

The same court in another drive at Patenga fined 54 vehicles Tk 2 lakh on the same ground on Monday.

Officials of Air Quality Management Project of DoE and traffic department of Chittagong Metropolitan Police assisted the mobile court.

Meanwhile, the same court yesterday fined 10 cargo-vessels, seized during separate drives at port channel on Sunday and Monday, Tk 3 lakh for risky movement with overloaded cement clinkers and chemical goods.

The fined vessels are MV Banglar Jihad, MV Mou-1, MV Golup-4, MV Salman Selim, MV Erfan Selim, MV Tiger of Comilla, MV Dewan Mehedi, MV Seven Circle-2, MV Master Saniyat-1 and MV Masud-1. The court suspended the movement of the vessels temporarily.