The police investigators could not yet reveal whether the bomb was categorized as high or low explosives, National Police Spokesman Inspector General Mohammad Iqbal said when contacted in Jakarta on Wednesday.
The crime scene investigation has involved the National Police's Densus 88 counter-terrorism squad, the North Sumatra Police's Indonesia Automatic Fingerprint Identification System (Inafis) unit and forensics units, he said.
The police are also probing into whether the suspect acted as a lone wolf or he belonged to a terrorist network, he said, adding that six people sustained injuries due to this bombing attack.
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However, none of them got serious wounds. All of the wounded survivors had been admitted to the North Sumatra police hospital for medical treatment.
Iqbal said the suspect walked into the yard of the Medan city police headquarters after the police officers finished holding their morning roll call. He walked toward an operational office, and then detonated the bomb.
When launching his attack, the suspect wore a jacket of an online-based motorbike taxi. Following this incident, security around the police headquarters which is located at MH Said Street was stepped up.
Several personnel of the police' Mobile Brigade Corps guarded the entrance gate and safeguard traffic access into the location. An ambulance was also on standby around the Medan city police headquarters.
In March this year, Solimah, a housewife, detonated a home-made bomb inside her house in Sibolga, North Sumatra Province.
Indonesia has become the target of attacks by terrorists since 2000, and the spread of extremism and terrorism continues to threaten the country.
ANTARA noted that in May 2018, a church in the East Java city of Surabaya was attacked. Three years ago, ISIS supporters in Indonesia had launched a suicide bombing and shooting attack in Jakarta on January 14, 2016, which led to the deaths of eight people, including three innocent civilians.
The incident adds to the list of deadly assaults conducted by terrorist cells in Indonesia. From 2000 to 2012, more than a dozen attacks took place in the capital city, including the Australian embassy bombing on September 9, 2004, and the JW Marriott and Ritz-Carlton hotel bombings on July 17, 2009.
One of the effective ways to free Indonesia from the vicious circle of radicalism and terrorism is by empowering women in the country, as they can actively contribute to safeguarding Indonesian children from being indoctrinated by terrorist recruiters.
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