Roman Catholics in Poland gathered for a special Mass celebrating what they see as a miracle: the appearance on a communion wafer of a dark spot that they are convinced is part of the heart of Jesus.



The communion wafer in question developed a brown spot in 2008 after falling on the floor during a Mass in the eastern Polish town of Sokolka. Two medical doctors determined that the spot was heart muscle tissue, church officials have said.



Bialystok Archbishop Edward Ozorowski said during the Mass that in history, the "substance of Christ's body or blood has become available to the human senses, and this also happened in Sokolka."



"For God, nothing is impossible," Ozorowski said.



The dark-spotted wafer was carried aloft in a reliquary by a golden-robed priest in a procession and was put on display in the town's church of St. Anthony as about 1000 faithful looked on, according to a report and footage carried by the TV station TVN.



Catholics believe that the bread and wine that priests use during the sacrament of communion - or the Eucharist - are changed into the body and blood of Jesus Christ.



The wafer was dropped by a priest celebrating communion in 2008. In accordance with church practice, the priest placed the wafer in water to dissolve it. Several days later a nun found that the wafer had not dissolved completely, and found a red mark on it.



The nun's discovery sparked huge interest among the faithful in this deeply Roman Catholic country, sparking large numbers to flock to Sokolka. Though some believers consider the object miraculous, the Vatican is still examining the matter and has not yet officially decided whether to declare it a miracle, church spokesman Andrzej Debski said.



A group of rationalists complained about the matter in 2008, and called on authorities to investigate if a murder or other crime was involved if human flesh was indeed found on the wafer. Police say they have no evidence of any crime.