Same thing happened in Romania.

The previous president was burning tens of million of Euros on renting private jets on the taxpayer's dime for trips that weren't related to his duties, and when reporters wanted to investigate this misuse, the government came forward and called the president's travel history (and expenses) a national security topic and remove it from the freedom of information.

Isn't it convenient how you can just cover corruption under the rug by invoking national security? I'm surprised it hasn't been used more often.