Not long ago, there was news in major newspaper about LTC scam. Here is the news appeared in the media
Central Vigilance Commission (CVC) has asked CBI to investigate a widespread racket in claims of leave travel concession (LTC) claimed by central government and public sector employees conniving with travel agents. Large sums are said to have been siphoned out of the government by producing fake Air India tickets and boarding passes.
While the aforesaid claim may be bogus in entirety, I am 100 % sure that all of them must have claimed exemption u/s 10(5) of the Income Tax Act and employers might also have not deducted any tax thinking that they have no role in judging the authenticity of the claim.