Bangladesh on Sunday blamed "homegrown" Islamist terrorists and Pakistan's spy agency Inter-Services Intelligence for the country's worst terror attack in which 20 hostages were hacked to death, ruling out the role of the Islamic State, as the shocked nation began observing two days of national mourning.
"Let me clear it again, there are no ISIS or al-Qaeda presence or existence in Bangladesh...the hostage-takers were all home-grown terrorists not members of ISIS or any other international Islamist outfits," said Home Minister Asaduzzaman Khan.
"We know them (hostage-takers) along with their ancestors, they all grew here in Bangladesh...they belong to homegrown outfits like JMB (Jamaatul Mujahideen Bangladesh)," he said.
The Islamic State has claimed responsibility for the killing of the hostages, mostly foreigners, and two police officers during the 12-hour siege that ended on Saturday after the army stormed the Holey Artisan Bakery popular with expats in the diplomatic zone, killing six attackers and capturing one alive.
Hossain Toufique Imam, the political advisor to Prime Minister Sheikh Hasina, said that the way in which the hostages were killed with machetes suggests the role of a local terrorist group, the banned Jamaat-ul-Mujahideen.
"Pakistan's ISI and Jamaat connection is well known... they want to derail the current government," Imam told a TV channel.
The arrested terrorist chickened out at the last minute and he holds the key to crucial details, he said.
Two teams of CID investigators and a bomb disposal squad visited the Spanish restaurant to collect evidence after Bangladesh's worst terror attack.
A police source was quoted as saying by the Dhaka Tribune that all the attackers were Bangladeshi nationals aged between 20 and 28. The plice said the attackers were well-educated and most came from rich families.
"All of them were students and communicated at the crime scene in both Bengali and English," the police source said.
Police chief AKM Shahidul Hoque said five of the dead gunmen were listed as militants and the police had been looking for them. The police identified them as Akash, Bikash, Don, Bandhon, and Ripon.
Hostages who were killed include 19-year-old Indian girl Tarishi Jain. Nine Italians, seven Japanese, one American of Bangladeshi origin, and two Bangladeshis were also among the people who were killed.
Bangladesh Prime Minister Sheikh Hasina vowed to trace the "roots" of the culprits who supplied weapons and explosives to the terrorists.
Her remarks came during a meeting with Japan's State Minister of Foreign Affairs Seiji Kihara at her official residence Ganabhaban.
Most of those killed were found with their throats slit.
Among those rescued were Indian, Sri Lankan and Japanese nationals, media reports said. Around 30 people were injured.
Meanwhile, Bangladesh Nationalist Party Chairperson Khaleda Zia called the Gulshan cafe attack a "cowardly act" and urged for a national unity to rid Bangladesh from militancy.
"All our achievement will go in vain if we cannot ensure security and eliminate militancy. Let us come forward, unite, forgetting all our differences," she said.
The government has consistently ruled out the presence of the dreaded terror group in the Muslim-majority nation though experts have been maintaining that series of brutal attacks on minorities and secular activists had the hallmarks of ISIS group.
The police have released the photos of the six gunmen killed during the raid by commandos. A seventh was arrested and is being interrogated by Bangladeshi intelligence officers.
Bangladeshi media reports said that after United States-based SITE Intelligence Group published photos of five gunmen holding assault rifles who, the Islamic State claims, killed the hostages, former classmates have started identifying by posting their old pictures on social media.
Warning "crusader countries" that their citizens would not be safe "as long as their aircraft are killing Muslims", the ISIS also posted pictures of four fighters, who it said were involved in the attack, smiling in front of a black flag of the outfit.
According to the reports, three of the five attackers have so far been identified by their friends.
The gunmen did a background check on religion of the captives by asking them to recite Quranic verses and tortured those who could not do so.
Announcing a two-day state mourning for those killed in the worst terror attack in the country, Prime Minister Hasina vowed to do everything to eliminate terrorists from the country and asked extremists to stop killing in the name of religion.
She asked all, including the general public, to get united to resist a "handful of terrorists".
The national flag was kept at half mast as the country began two-day mourning period.
A huge number of people joined the mourning wearing black badges or posting black badges on their social media accounts, including Facebook.
Hasina will also pay her respects to the victims of the terror attack at Gulshan cafe in a ceremony on Monday. The ceremony will be held at the army stadium in Dhaka.