Sorry about your birds and your grief.
Years ago my father complained to a neighbor a half mile away about his chicken stealing dog. The dog owner insisted that the dog never left the yard, my father must be mistaking it for another.
My father peppered the offender's hind quarters with bird shot when it was in the hen house the next day.
Being a small town, the local vet called my dad to let him know he spent the better part of the day picking the shot out while the family's children cried. The neighbor was certain someone had driven by his yard and shot his dog out of malice.
Soon we saw that the dog had returned to our farm, this time during the night. Dad brought it (covered in blood) and the dead birds to the neighbor in the middle of the night making certain he woke the kids up too. He stated that while he appreciated this was a loved family pet, he was within his rights to not use bird shot next time.
The dog was kenneled.
It can be quite frustrating dealing with a neighbor's animal. If it is a stray you will not have to worry about these ramifications. Make disposal as quick and painless as you can.