The attackers who vandalised and torched four Hindu houses and a family temple in Korbanpur village of Cumilla's Muradnagar on Sunday, did so even as the issue that inflamed them -- a Facebook post that they said hurt religious sentiments -- was being resolved.

Locals said most of them were outsiders who had arrived on Saturday evening and asked them over a loudspeaker to join them in a protest rally.

In the recent Facebook post in question, Shankar Devnath, a head teacher of a local kindergarten school had reacted with a heart emoji. One other local shared the post.

However, police had already arrested the two by Saturday night and yet, attackers gathered on the Korbanpur High School premises and later attacked and torched four houses and a temple on Sunday, said locals.

One of the four houses belonged to Bon Kumar Shib, chairman of Purbo Dhoir union parishad of the same upazila. When the attack took place, locals said he was holding a meeting with religious leaders of the area to inform them that the two had been arrested.

This correspondent visited the spot yesterday and found at least four houses -- belonging to Shib, Liton Kumer, Sawndip Das and one of the two arrestees -- and a family temple vandalised and torched.

"On Sunday noon, I was at Khusghor village [adjacent to Korbanpur]. At around 1:00pm, I suddenly heard a voice over loudspeaker asking people to join a rally," said Jamshed Sarker, member of ward-9 of Purbo Dhoir union parishad.

"Later, around 3:00pm, I came to the rally and saw several hundred people had gathered there. But most were unknown faces," he said.

At around 3:45pm, some people suddenly broke off from the gathering and attacked the Hindu houses, Jamshed told The Daily Star yesterday.

Abdul Mannan, a resident of Jamgarh village, adjacent to Korbanpur, said, "I noticed that people started gathering at the high school premises since around 1:00pm. Most came from outside the area. But we could not imagine that such a heinous attack would be launched from the rally."

"The union parishad Chairman Bon Kumar Shib is a popular leader in our area and he has completed many development activities here. Some vested quarters may be unhappy over his popularity. That may be a reason behind the attack," said Abul Kalam Bhuiyan, a resident of Khusghor village and general secretary of the union unit Awami League (AL).

Later, on Monday, three cases were filed with Muradnagar upazila's Bangora Police Station in connection with the attacks, said Kamruzzaman Talukder, officer-in-charge (OC) of the police station.

Victims Bon Kumar Shib, Liton Kumer and Sawndip Das filed the three cases against 91, 87 and 84 named and unnamed persons respectively.

Earlier, hours after the attack on Sunday night, police arrested five youths from Korbanpur village for their involvement in the attack.

They are Shanu, 38, Ershad Mia, 40, Enu Mia, 48, Babu Mia, 23, and Helal Uddin, 50.

Police said they seized bamboo sticks, lethal weapons from them.

Of the five, three were sentenced to 18 months' imprisonment and two were sentenced to six months in prison by a local mobile court led by Saiful Islam Komol, assistant commissioner (land) and executive magistrate.

The district administration on Monday formed a three-member probe body to investigate the incident.