The Władysław Mazurkiewicz Serial Murders
Władysław Mazurkiewicz cultivated the appearance of a prosperous, well-connected Kraków businessman while committing crimes for financial gain. In 1956 he was tried and convicted of six murders and two attempted murders. Later stories attributed far more deaths to him, but those larger numbers were not established by the judgment and are not counted here as proven victims.
Władysław Mazurkiewicz became one of the best-known defendants in postwar Polish criminal history. He was associated with Kraków's affluent social world and later acquired press nicknames emphasizing his polished appearance. Those labels can obscure the more important fact: the criminal court record ultimately concerned six murders and two attempted murders, committed in a pattern driven by money and property.
A long pattern hidden behind status
Historical reporting describes Mazurkiewicz as moving comfortably among restaurants, hotels, gamblers, currency dealers and people involved in unofficial trade. The image of wealth and social confidence helped him gain access to people who possessed cash, jewelry, foreign currency or other valuables.
Accounts of the crimes describe more than one method. Poison was used in at least one attempted killing, while firearms featured in later attacks. The common thread identified in historical sources was material gain, not a single ritualized method.
Attempted victims who survived
The survival of intended victims was central to ending Mazurkiewicz's impunity. Tadeusz Bommer testified about a wartime poisoning attempt after consuming food provided during a supposed financial transaction. He survived and later described the episode at trial.
More than a decade later, Stanisław Łopuszyński survived being shot during dealings that had begun around an alleged watch purchase. Doctors later removed bullets from his head. His report to authorities became a decisive lead, and Mazurkiewicz was eventually located and arrested.
The investigation and charges
The investigation expanded beyond the surviving victim's complaint. Authorities connected Mazurkiewicz to multiple earlier deaths and gathered witness testimony, property evidence and accounts of financial dealings. By the time of trial, prosecutors accused him of six completed murders and two attempted murders, along with additional offenses.
That number is the editorial ceiling for the victim count in this file. Modern Polish Radio notes that some people later attributed as many as 30 killings to him. Those broader allegations are part of the mythology surrounding the case, not the adjudicated record. No additional victim is presented here as a proven murder merely because a later writer suspected a connection.
The 1956 Kraków trial
The trial opened in Kraków in August 1956 and drew intense public and press attention. A detailed historical reconstruction by Tygodnik Powszechny places the opening on August 6 and follows testimony across the month. Mazurkiewicz initially maintained statements he had made during the investigation, then near the end of the proceedings attempted to withdraw them and assert innocence.
The court did not accept that late reversal. On August 30, 1956, Mazurkiewicz was convicted. Contemporary and later historical accounts describe multiple death sentences corresponding to the serious crimes for which he was held responsible.
Supreme Court review and execution
The judgment did not end with the trial court. Historical reporting records that Poland's Supreme Court upheld the sentence roughly two months later. A clemency effort did not prevent execution.
Mazurkiewicz was executed at Kraków's Montelupich prison on January 29, 1957. Some popular accounts have circulated a January 31 date, but the more carefully sourced historical reconstructions used for this file identify January 29. Where historical retellings conflict, this archive favors the chronology supported by multiple stronger sources.
What is proven, and what remains allegation
The court-established core is clear: six murders and two attempted murders. The conviction survived Supreme Court review and the sentence was carried out. That supports the archive classification Solved / Final conviction.
Claims that Mazurkiewicz killed dozens of additional people are not treated as judicial fact. Nor does this page present every unexplained disappearance from his social circle as one of his crimes. Historical crime writing can preserve suspicions and unanswered questions, but it cannot substitute them for proof.
Why the case remains historically significant
The case exposed more than a sequence of killings. The trial also drew attention to illicit postwar commerce, social networks built around scarce goods and foreign currency, and the ability of a socially confident offender to remain outside effective scrutiny for years. Reporters and writers later turned Mazurkiewicz into a symbol of Kraków's criminal underworld, sometimes adding legend to the documented record.
For Crime by Region, the editorial value lies in separating those layers: the six murders and two attempts established in court; the investigative history that led to arrest; and the larger, unproven victim-count claims that must remain labeled as speculation.
Timeline
- Tadeusz Bommer survives a poisoning attempt
Bommer later testifies that he became ill after food provided during a transaction involving Mazurkiewicz.
- Murders and financial crimes accumulate
Investigators later connect Mazurkiewicz to a series of killings committed for material gain.
- Stanisław Łopuszyński survives
A shooting victim survives, receives medical treatment and reports the attack, accelerating the investigation.
- Trial opens in Kraków
The high-profile proceedings begin before a crowded court and intense press attention.
- Conviction and death sentence
Mazurkiewicz is convicted in the case covering six murders and two attempted murders.
- Supreme Court upholds the judgment
The death sentence survives review.
- Sentence carried out
Mazurkiewicz is executed at Montelupich prison in Kraków.
“Six murders and two attempted murders” is the court-supported figure used here. Reports that he may have killed 30 or more people are clearly identified as unproven and are not added to the victim count.