The Russian Investigative Committee confirmed her death, and is probing her mystery fall.
She is the latest of many Russians to have plunged to their deaths during Putin’s long rule.
Before joining the Western Military region, Yankina worked in the Federal Tax Service, and also served as Deputy Chairman of the Property Relations Committee of St Petersburg.
Suicide is suspected, according to reports, but this is often stated in such cases before any investigation is carried out, or the facts are known.
The woman is believed to have been at the centre of efforts to boost funding for a war unleashed by Putin which has led to hundreds of thousands of deaths.
Initial reports suggest she did not live at the building.
Her personal belongings were found on the 16th floor of the building, and it is believed she fell from there.
Yankina was reported to be close to Mikhail Mokretsov, former Chief of Staff of the Ministry of Defence and Deputy Minister of Defence.
He is a Russian businessman and state official who served as Director of the Federal Taxation Service from 2007 and 2010, and was later a senior official in St Petersburg.
Media outlet Mash on Moika, with links to law enforcement, carried a claim that Yankina fell from the balcony of her ex-husband’s home.
“Shortly before the fall, the deceased employee of the financial sector of the Western Military District called her ex-husband,” said the outlet.
“A few minutes after the call, she was found dead.
“According to our information, the husband lived in the block from the balcony of which the fall occurred.
“The motives continue to be clarified - according to the latest data, the woman had health problems.”
There was no independent confirmation of this version of her death.
“Her career had developed rapidly,” stated the outlet.
“In five years, a woman rose from an ordinary employee to the head of the entire department.
“Meanwhile, the death of the employee was officially confirmed by the press service of the Western Military District.”
