As part of a joint investigation between Thames Valley Police and Polish law enforcement, two men have been extradited to Poland for court proceedings in connection with the murder of Andrzej Mucha, a Polish national, in Slough.

Andrzej was reported missing from Slough on 30 December 2021 and enquiries led to this becoming a Murder investigation in April 2022. Despite Mr Mucha remaining missing, in January 2023, Thames Valley Police charged Adrian Pietraszewski, aged 28, and in February 2023, Tomasz Grzegorz Weiss, aged 36, with one count each of preventing a lawful burial of a dead body and one count of perverting the course of justice.

Later that month, Thames Valley Police, the Crown Prosecution Service and Polish prosecutors signed a joint investigation agreement in The Hague and began to work together on the investigation. Polish law enforcement – Circuit Prosecutor’s office in Gliwice – was then able to gather new and compelling evidence linking Pietraszewski and Weiss to Andrzej’s murder.

This evidence would not be admissible in UK courts, therefore a decision was made by Thames Valley Police and the Crown Prosecution Service to discontinue court proceedings in the UK in order to allow the extradition process to commence to enable a trial in Poland for the more serious offence of murder.

At the High Court in London on 12 November 2025, Justice Hilliard ruled that Adrian Pietraszewski, and Tomasz Grzegorz Weiss,  both Polish citizens, will be extradited to Poland where there will be court proceedings in connection with the murder of Andrzej Mucha.

The pair appealed the decision, but that appeal was dismissed.

Pietraszewski was extradited on 13 January this year and Weiss was extradited on 26 February 2026.

In early February, Polish law enforcement supported Thames Valley Police in carrying out searches in a field on Grays Park Road, Stoke Poges, Buckinghamshire.

Sadly, during these searches human remains were discovered and these have now been formally identified as that of Andrzej Mucha.

Andrzej’s family are being supported and kept up to date regarding the progress of the murder investigation. Please see their tribute to Andrzej below.

Thames Valley Police is continuing to support Polish law enforcement with its ongoing investigation into Andrzej’s murder, and has shared the evidence gathered during the force’s initial large scale missing person and subsequent murder investigation.

Polish law enforcement has also made further arrests in connection with this investigation.

Head of Thames Valley Police’s Major Crime Unit, Detective Superintendent Kevin Brown said: “Thames Valley Police has carried out a very thorough and complicated investigation, initially as a missing person’s case and latterly as a murder investigation.

“We have continued to follow new lines of enquiry, which recently lead to the discovery of Andrzej’s remains in Buckinghamshire.

“With Polish law enforcement support, who gathered new and compelling evidence linking Adrian Pietraszewski and Tomasz Grzegorz Weiss to Andrzej’s murder, we have worked tirelessly with the Crown Prosecution Service and Polish authorities to secure a landmark decision to discontinue legal proceedings in the UK and extradite the defendants to Poland to stand trial there.

“Our thoughts remain with Andrzej’s family, who have shown great patience and confidence in the force and our partners.

“We will not make any further comment ahead of the trial in Poland.”

Tribute from the family of Andrzej Mucha

Andrzej Mucha is much loved son, brother, husband, father and grandfather and despite his life being taken, he very much remains so. The cruel way he was taken from our lives will never win over the love he had for each one of us.

In addition to loving and being loved by so many family members; he impacted everyone’s life that he came into contact with. Andrzej was such a friendly person, each person he met would feel the care and love he felt for them, he’d pour his heart into each friendship.

He was helpful, trustworthy and could make you laugh in a heartbeat. He was able to create Michelin-starred food out of barely any ingredients. His mini-pizzas were legendary, and his pierogi were heavenly for taste buds.

Andrzej loved sports and enjoyed football himself.

He was a dreamer; he enjoyed playing scratch cards and never lost the hope that he’s win £1 million one day and be able to rest. I know he’d give up that million pound dream just to spend one more day with us, or comfort us during this incredibly sad time.

Whilst my dad, was all of these things and a great man with such a big heart. He was simply ‘our little Andrzej’.

Whilst, this is a sad time to say goodbye there’s so much more I would like to say to my dad. I want to say: “Thank you for every moment we have spent together.” These are really precious memories that I will treasure that no-one can take away.

Your life was an incredible gift, and it was cruelly taken away from us all too soon. However, you will forever remain in our hearts, and your smile will remain in our memories – always.

The world is a much sadder place without you being here with us. The pain we are all experience now, is a testament to the love that we once shared and now all desperately miss.

You will live on, in your children and grandchildren’s lives. We will continue to teach our children the kindness and love that you showed us.

When my dad lost his life, the world lost a good man. In that second, I lost my first hero. But his love was so strong, no-one could extin