A poppy appeal box was stolen from a Lancashire church on Remembrance Day, police have said.
The collection box was taken from St Oswald's Church in Longton, Preston, on Thursday between 1130 and 1520 GMT.
Lancashire's poppy appeal co-ordinator Michael Turner said the theft "on the most solemn of days" was "truly despicable".
Insp Astrid Robinson, of Lancashire Police, added: "This callous thief has no conscience."
"They have gone into a place of worship and stolen monies destined for those who have sacrificed much whilst serving in the nation's Armed Forces."
She urged anyone with information to contact police.
Father Leo Cooper is donating £100 to the poppy appeal to compensate for the loss, police said.