A Supreme Court order banning the use of polluting diesel-run buses meant that half the city's bus fleet has been grounded, stranding commuters.

The city government ordered schools to shut for two days in an attempt to ease commuter congestion.

Last week the court said it would fine transport operators who had failed to meet a deadline to switch to cleaner fuel.

The court also rejected an appeal by the bus owners seeking extra time to convert their fleet to the environmentally friendly compressed natural gas (CNG).

Thousands of commuters faced longer than usual delays in reaching their workplace.

"The bus came after an hour and there was no place so we had to walk for an hour," said one commuter.

Those who chose to use taxis and three-wheel motor rickshaws were forced to pay extra.

Appeal

Transport operators said they could not afford to junk their old buses and buy new ones without financial assistance.

"The economics of this are just not working out," said Jaswant Singh, the head of the city's transporters' union.