Pope John Paul cruising in Popemobile
Pope John Paul II cruises through Rome in a bulletproof popemobile in 2005. Reuters/Tony Gentile DJM/ABP

For many a vacationer, a souvenir could be a T-shirt or a trinket, but for one recent visitor to Germany’s Cologne Cathedral, it was something much more valuable: An unknown suspect stole from the church a cloth with a drop of Pope John Paul II’s blood, the Associated Press reported Sunday.

The cloth had been stored inside a glass container at the base of a sculpture to commemorate the pope’s 1980 visit to the cathedral, and the thief pried the glass container from its resting place, according to police. Authorities at the church became aware the relic was missing when a visitor alerted an usher to its absence.

“The material value is small, much greater is the spiritual loss,” Gerd Bachner, the cathedral’s provost, said in a statement pleading for the object’s return, NBC News reported.

John Paul II was born in Wadowice, Poland, in 1920 and made history in 1978 when he became the first non-Italian pope to serve in the position in more than 400 years. He would lead the Roman Catholic Church until his death in 2005, leaving behind a legacy of fighting for human rights.

The incident in Cologne did not mark the first time thieves stole a relic related to John Paul II’s blood. After a 1981 assassination attempt, three relics emerged from the bloody cassock the pontiff was wearing that day.

One relic was housed in a church in San Pietro, Italy. Thieves broke a window and entered the church in 2014, stealing the relic and a simple cross while leaving behind the collection box and several items of greater monetary value. The relic was eventually discovered in a nearby garage.

I think John Paul has forgiven them. I think we have to do the same,” Auxiliary Bishop Giovanni D’Ercole of L’Aquila said at a press conference at the time, the Catholic News Agency reported.