The arrestees were Rakibul Hasan, 22, son of Abul Kalam Molla and Saikat Mridha, 22, son of Sunil Krishna Mridha of Najirpur upazila of Pirojpur.
Upazila unit BCL general secretary Md Al Amin Sheikh has acknowledged the matter.
He said that they are BCL activists and followers of Pirojpur district unit Awami League president and former lawmaker Awal.
Mukit Hasan, additional superintendent of Pirojpur Police (Crime & Operation), said police arrested Mridha from Narayanganj and Rakibul from Pirojpur district on Friday.
There is a tense situation had been prevailing in the locality in Najirpur upazila over making indecent comments about Prophet Hazrat Muhammad (PBUH) on their facebook pages, he said.
Following the facebook posts, 12 Shibir activists went to the house of Saikat over the issue that spread panic among locals.
A team of Army rushed to the spot and brought the situation under control.