Commercial vehicle drivers were responsible for at least 35% of the 7,281 road accidents in Delhi last year that claimed over 2,000 lives.
And now, the transport department has found that scores of them got licences using fake learner's permits or without mandatory road tests.
The department received several complaints against the Wazirpur and Sheikh Sarai transport authorities and, on checking, found irregularities in the way licences were being issued.
"We received many complaints and our vigilance wing is probing," said RP Meena, joint commissioner (transport), Delhi.
A transport department official said inspectors were found not conducting road tests and simply approving the applications. The official said the form to be filled up before the test must have essential information, such as the vehicle's registration number and the applicant's details. The inspector must grade the applicant's performance.
"In almost all the forms we checked, these details were missing. The inspectors had just signed the forms," the official said.
"It cannot be ruled out that the inspectors took bribe to issue licences. Workload too could be a reason behind their casual approach," the official said.
To get a commercial licence in the city, one must be at least 20 and should have done a month's training at a driving school.