The group that has claimed responsibility online for the murder of two expatriates recently also claimed responsibility for the slaying of several free-thinking bloggers earlier, an information technology expert who assisted in the investigations said on Monday.
The IT expert said there was evidence the tweeters had received funds from the Middle East.
“Those trying to create anarchy in the country by killing bloggers are the same people as those claiming responsibility for killing foreigners,” said Tanvir Hassan Zoha, director of operations at Insight Bangladesh Foundation and focus person of the Cyber Nirapotta Programme under the Information and Communications Technology Division.
“They can call themselves IS, al-Qaeda, Ansarullah Bangla Team, Jamaat-Shibir or whatever, but they belong to the same group,” Tanvir said.
He said “electronic evidence” showed that the tweet claiming responsibility for the Tavella murder was uploaded from Dhaka's Gulshan neighbourhood and that there was evidence that funds had been received from Saudi Arabia.
DB Investigators disagree with Tanvir's claims.
They said they had not found any evidence linking the blogger murders to the foreigner murders and said the two types of incidents were completely different.
About Tanvir's claim, DB investigators said the murders were still under investigation and that it was too early to comment further.
Cyber Nirapotta Programme Deputy Programme Director Mohammad Anwar Hossain said: “Tanvir worked on the programme until June 1, and helped the Detective Branch with their work with special permission.”
Tavella murder
The DB's cybercrime cell investigating the murders said the tweets claiming responsibility for the murders were tweeted from Dhaka and Rangpur, respectively.
Investigators yesterday said they had put at least four people, including the person who might have tweeted the IS claim link after the Tavella murder, under surveillance.
A DB source said 20 people had earlier been put under surveillance and three people, the likely murder suspects in the Tavella murder case, had been tracked down.
DB sources said they had found the person, identified only by the surname “Rakib,” who issued the Dhaka tweet. Police have not yet determined whether he is connected to a militant group.
DB does not yet have information on the Rangpur tweeter.
Police yesterday said they had made a breakthrough in the case but declined to remark further about the development.
The DB source said ballistic reports and other evidence will be used to determine whether those under surveillance were involved in the murders.
Dhaka Metropolitan Police (DMP) Detective Branch (DB) Additional Deputy Commissioner Mahfuzul Islam said: “We have made some breakthroughs in the case and are working to ascertain that everything is going in the right direction.”
He declined to comment further.
IS claims
The DB source said investigators had contacted Rita Katz, director and co-founder of SITE Intelligence Group, about the IS claims the group had publicised.
The DB source said Katz did not provide information about where she had found IS' claims of responsibility. She told them she received the information through separate tweets issued the day the foreigners were murdered.
Katz told the DB that on September 28, a tweet was seen around 1:30pm US Eastern Standard Time and published on the SITE website within half an hour.
On October 3, around 11:30pm she saw a similar tweet claiming responsibility for the murder of a Japanese citizen and published it on the SITE website.
She, however, declined to provide further information.
On October 9, Rita Katz tweeted: “My advice to security agencies in #Bangladesh is not to dismiss these claims or deny the presence of #ISIS followers in their country.
“What’s happening in Bangladesh, like other countries, is the effect of ISIS’ highly effective propaganda and outward growth.
“These things considered, are #ISIS ’ claims that surprising? Is #Bangladesh somehow immune to what countries all over the world aren’t?”
Hoshi murder
In the Hoshi case, police detained ten people and showed two of them arrested in the case. Two are in jail and the other is in remand.
Four detainees have been let go and three others remain in police custody.
The three-member Japanese team that went to assist the Hoshi murder probe returned to Dhaka yesterday. Another two-member team left yesterday for Rangpur. The Japanese national's place of burial remains an unresolved issue.
Japanese citizen, Hoshi Kunio, 65, was shot dead by three unidentified assailants on October 3.
Italian citizen Cesare Tavella, 51, was shot by three unidentified assailants on September 28 and died on the way to United Hospital in Gulshan.
From February this year, four bloggers have been killed in Bangladesh.
On August 7, blogger Niladri Niloy was killed at his residence in Khilgaon. His murder occurred two months after blogger and writer Ananta Bijoy Das was hacked to death on a street in Sylhet city on May 12.
Secular activist Oyasiqur Rahman Babu was hacked to death in the capital by three people on March 30.
On February 26, Mukto-Mona blog founder and former Buet teacher Avijit Roy was killed by religious extremists during Ekushey Book Fair. His wife Rafida Ahmed Bonya sustained injuries during the attack. Both held US citizenship.
Earlier, Rajshahi University teacher Prof AKM Shafiul Islam was killed on November 15 last year. Daffodil University student and secular activist Ashraful Alam was killed on September 30 last year while war crimes trial campaigner Ahmed Rajeeb Haider was murdered on February 15, 2013.
Secular writer Asif Mohiuddin was attacked on January 13, 2013 and Rakib Mamun on June 24, 2014. They narrowly escaped death.
Al-Qaeda in the Indian Subcontinent claimed responsibility for the murders in May, but police believe outlawed militant outfit Ansarullah Bangla Team is responsible.