In November 1953, First Secretary of the Polish United Workers' Party, Bolesław Bierut, asked Politburo member Jakub Berman to send MBP Lieutenant Colonel Józef Światło on an important mission to East Berlin.
Światło, deputy head of UB Department 10, together with Colonel Anatol Fejgin, were asked to consult with the East German Ministry for State Security's chief Erich Mielke about eliminating Wanda Brońska.

The two officials traveled to Berlin and spoke with Mielke.
On December 5, 1953, the day after meeting Mielke, Światło defected to the United States through their military mission in West Berlin.
The next day, American military authorities transported Światło to Frankfurt and by December, Światło had been flown to Washington D.C, where he underwent an extensive debriefing.

Światło's defection was widely publicized in the United States and Europe by the American authorities, as well as in Poland via Radio Free Europe, embarrassing the authorities in Warsaw.
Światło had intimate knowledge of the internal politics of the Polish government, especially the activities of the various secret services.
Over the course of the following months, American newspapers and Radio Free Europe reported extensively on political repression in Poland based on Światło revelations, including the torture of prisoners under interrogation and politically motivated executions.
Światło also detailed struggles inside the Polish United Workers' Party.

Among other activities, Światło had been ordered to falsify evidence that was used to incriminate Władysław Gomułka, whom he personally arrested.
He had also arrested and falsified evidence against Marian Spychalski, the future Minister of National Defence, who was at the time a leading politician and high-ranking military officer.
In November 1953, First Secretary of the Polish United Workers' Party, Bolesław Bierut, asked Politburo member Jakub Berman to send MBP Lieutenant Colonel Józef Światło on an important mission to East Berlin. Światło, deputy head of UB Department 10, together with Colonel Anatol Fejgin, were asked to consult with the East German Ministry for State Security's chief Erich Mielke about eliminating Wanda Brońska.
The two officials traveled to Berlin and spoke with Mielke. On December 5, 1953, the day after meeting Mielke, Światło defected to the United States through their military mission in West Berlin. The next day, American military authorities transported Światło to Frankfurt and by December, Światło had been flown to Washington D.C, where he underwent an extensive debriefing.
Światło's defection was widely publicized in the United States and Europe by the American authorities, as well as in Poland via Radio Free Europe, embarrassing the authorities in Warsaw. Światło had intimate knowledge of the internal politics of the Polish government, especially the activities of the various secret services. Over the course of the following months, American newspapers and Radio Free Europe reported extensively on political repression in Poland based on Światło revelations, including the torture of prisoners under interrogation and politically motivated executions. Światło also detailed struggles inside the Polish United Workers' Party.
Among other activities, Światło had been ordered to falsify evidence that was used to incriminate Władysław Gomułka, whom he personally arrested. He had also arrested and falsified evidence against Marian Spychalski, the future Minister of National Defence, who was at the time a leading politician and high-ranking military officer.
Ministry of Public Security (Poland)