The number of complaints received by aviation regulator Directorate General of Civil Aviation (DGCA) in July was 581 compared to 900 in June, official data showed.
Almost 30 percent of passenger complaints related to troubles with flight cancellations or delays, while about 25 percent of passengers expressed discontentment over customer services of various airlines, the July data showed.
The percentage of complaints about staff behaviour in July was 11.5 percent, compared with 7.9 percent in June.
While lost baggage complaints totalled over 18 percent in July, it was 23 percent in the previous month.
Officials said these complaints have led the DGCA to tighten the screw on airlines, especially on checking instances of rude or unhelpful behaviour of their staff at airports and in the aircraft.
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