A university student blew himself up in a suicide bombing outside police headquarters in the Indonesian city of Medan on Wednesday, police alleged.

The attack came just one month after an Islamist militant attacked a former security minister.

The details

The explosion happened at around 8:40 a.m. local time (0140 UTC)

The blast killed the attacker and injured six others — four police officers and two civilians

Police say the blast happened in a parking lot near where people were in line waiting for clearance letters

The motive of the 'lone-wolf' attack was not immediately clear

Ongoing investigation

Local police spokesman Dedi Prasetyo said security procedures had been in place, but the attacker ignored instructions when officers tried to check his backpack.

The national Densus 88 anti-terrorism unit said it was investigating whether the 24-year-old bomber had any links to radical

groups such the Islamic State-inspired Jamaah Ansharut Daulah.

Read more: Southeast Asia in the crosshairs of 'Islamic State'

Increased threat: Indonesia is the world's largest Muslim-majority country. It has suffered a string of terrorist attacks since the turn of the century. More recent strikes have been blamed on Islamic State-inspired militants. Indonesia's counterterrorism force has so far arrested 40 suspects since receiving a tip last month about potential attacks on police facilities. In August, authorities shot and arrested a militant who attacked officers at a station in Surabaya. In June another was seriously wounded when he tried to blow himself up outside a police building on Java island.

aw, dv/se (AFP, dpa, Reuters, AP)

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