In an October 17 Facebook post, NABU said it had detained Oleh Hladkovskiy, the former first deputy secretary of the National Security and Defense Council (NSDC), on charges that are punishable by up to 8 years in prison and the prohibition of holding certain government positions for three years.

Further information about the case is being withheld in order to keep the investigation confidential, NABU said.

Former parliamentary deputy Serhiy Leshchenko said earlier in the day on social media that NABU had taken Hladkovskiy at a restaurant outside Kyiv near the Boryspil Airport.

Poroshenko dismissed Hladkovskiy from his post at the NSDC in March after a series of investigative reports by local journalists found that Hladkovskiy was allegedly linked to a large-scale embezzlement scheme involving procurement in the defense industry.

The scandal erupted a month before this year's presidential election and adversely affected Poroshenko's chances of reelection.

Hladkovskiy and his son, Ihor Hladkovskiy, who also featured in the reports as being directly involved in the scheme, have denied any wrongdoing.

The scheme partially involved selling smuggled Russian components to Ukrainian defense plants at inflated prices.

Amid an armed conflict with Moscow-backed separatists in eastern Ukraine, Kyiv’s defense budget has skyrocketed from $3.3 billion in 2014, when the Donbas war started, to $7.8 billion this year.

About $630 million of this year’s amount was earmarked for the procurement of weapons and military equipment.