Detectives took around eight years just to analyse  footage and collect evidence of the mayhem Hefajat carried in 2013 as it was a "big incident", said AKM Hafiz Akter, additional commissioner of the Detective Branch of Dhaka Metropolitan Police.

He said this while responding to a reporter's query at the media centre in the capital's Minto Road yesterday.

The accused in the cases related to the incident are now being arrested in the wake of the investigation, but it may take some more days to complete the probe, said Hafiz, also the chief of DMP DB.

He said, "We did not want any innocent person to face punishment. Therefore, we are investigating the cases after analysing all confessional statements."

However, investigation of the cases has speeded up and will be complete soon, he said.

Regarding the ongoing drive, he said Hefajat has been carrying out violence in different places, including Dhaka and Brahmanbaria, centring Indian Prime Minister Narendra Modi's recent visit to Bangladesh.

"Our law enforcement's task is to prosecute perpetrators of sabotage and bring them under the law following investigation. Police are now being able to bring into custody those who were found involved in the incident, after analysing video footages. They are also now conducting further investigation," he said.

Police officials claimed that not a single innocent person has been arrested so far. They are looking for those who are definitely guilty of the crimes committed during the incident.

According to sources, even this year, 17 people were killed in violent clashes carried out by Hefajat in different parts of the country from March 26 to 28.

Following that, the investigation into 62 pending cases filed since the 2013 mayhem has seen updates and central Hefajat leaders are now being shown arrested in those cases. 

Around 83 cases were filed in 2013, but police have pressed charges only in 18, and gave final reports in two. Investigations of the remaining 62 have been stalled for past eight years.

Police Headquarters sources said around 143 cases were filed after the violence on March 26 to March 28. Over 900 people, mostly Hefajat supporters and 29 top central leaders, were arrested in the old and new cases.

In the wake of the arrests, Hefajat yesterday demanded the release of "Ulemas and general religious people" who were arrested over the violence by the Islamist organisation in March during demonstrations against the Indian PM's visit.

A 10-member Hefajat delegation, led by its secretary general of the convening committee Nurul Islam Jihadi, placed a four-point demand before Home Minister Asaduzzaman Khan during a meeting with him at his city residence.

Meanwhile, the DB of Chattogram district police arrested the former publicity secretary of Hefajat over the mayhem during the anti-Modi protests at Chattogram's Hathazari on March 26, reported our Chattogram correspondent.

Jakaria Noman Fayeji, the central leader, was held from Chakaria upazila of Cox's Bazar, said Abdullah Al Masum, Additional Superintendent of Police.

On the other hand, three former leaders of Hefajat-e-Islam were placed on different terms of remand yesterday in four separate cases filed with Motijheel, Paltan, Shahbagh and Ramna police stations over the 2013 mayhem in Dhaka.

The leaders are Hefajat's former assistant secretary generals Mufti Shakhawat Hossain Razi and Maulana Monzurul Islam Afendi, and Assistant Organising Secretary Ataullah Ameeni.

Both Shakhawat and Monzurul were placed on a three-day remand each, in a case filed with Paltan police. Shakhawat was also placed on a three-day remand in another case filed with Motijheel police.

Besides, Ataullah was placed on a three-day remand separately in two cases filed with Shahbagh and Ramna Police Stations.