- "Quite often, with MPs and officials, if the source of their money isn't clear, they register assets to people close to them," explains Tkach.
- The journalist also published footage which appeared to show the official driving an expensive Porsche for a few months.
It's been a political reshuffle with a difference.
At the time of typing this, 11 officials have either resigned or been sacked as Kyiv tries to tackle government corruption.
It's led to some politicians in the US calling for aid to Ukraine to be restricted.
President Volodymyr Zelensky is trying to quickly restore public faith, but the allegations are serious, and the timing is bad.
Several claims have surfaced thanks to Mykhaylo Tkach, an investigative journalist for the news website Ukrayinska Pravda.
He has recently reported that the company of a senior official's personal trainer allegedly received millions of pounds since the full-scale invasion, as well as a story about President Zelensky's deputy head of office.
Kyrylo Tymoshenko quit two months after Tkach reported that he'd moved his family to the mansion of a well-known property developer.
The journalist also published footage which appeared to show the official driving an expensive Porsche for a few months.
Mr Tymoshenko has denied doing anything wrong.
"Quite often, with MPs and officials, if the source of their money isn't clear, they register assets to people close to them," explains Tkach.
"These are signs of non-transparency, at a time when every step of an official should be clear for society."
The reporter concedes corruption exists in many countries. It's why he thinks the reaction to it is most important.
From her bakery in Vorzel, near Kyiv, Ivanna is less than impressed with her government being accused of paying inflated prices to an unknown firm, a minister allegedly accepting a bribe worth £300,000 ($372,000), and an official's expensive taste in cars.
"I don't like it," she says, while her husband Vyacheslav stirs dough in the back room.
"It would be better for this money to go towards something good for Ukraine."
She pauses: "We need to replace all those politicians who've been there for many years. They've got used to it; it feeds them."
For Ukraine, receiving billions of dollars in military, humanitarian and financial aid brings responsibility and scrutiny.
It also increases the likelihood of money ending up in the wrong hands.
"We are talking about Ukraine's existence," says Tkach. "It's not just some ordinary year for our country. So, I think this wave of resignations, initiated by the president, is an important acknowledgement and necessary action."
Ever since Ukraine declared independence 31 years ago, corruption has plagued its public services and most of all its politics.
In 2014, a popular revolution toppled the last Moscow-leaning government because people wanted to finally live under a democracy.
Ever since, Ukraine has attempted a series of reforms, notably driven by Russia's subsequent campaign of aggression towards the country. Change was seen as essential to securing the West's continued support.
New anti-corruption agencies were then set up, along with new systems for government spending, a new police force, and politicians were forced to disclose their wealth - often with eye-watering confessions.
"We wanted results," Yaroslav Yurchyshyn tells me. He's an MP and deputy head of the parliamentary anticorruption committee.
"Yes, we have some leftovers from corruption in the past, but at least now we are not silent about it. The next stop will be prevention."
Mr Yurchyshyn believes there's no better time to expose ministerial wrongdoing, even with Western help being put at risk.
"Western partners understand we have two wars," he says. "The first is against Russia, then there's our internal war for the future of Ukraine."
Before the full-scale Russian invasion of February 2022, Western allies like the European Union and the US weren't happy with the pace of Kyiv's efforts to combat corruption.
While it's not clear what the political damage of the 2023 allegations will be for President Zelensky, his response to them this time has been described as "quick and decisive" by the US.
With more allegations expected to surface, he'll be hoping other supporters feel the same.