The blasts occurred at 9:10 a.m. local time, and the trial scheduled for Abdurahman was suspended for three minutes.
Densus 88, the police`s anti-terror squad, guarding the courtroom called on the audience to remain calm.
South Jakarta`s Police Chief Senior Commissioner Indra Jafar noted that the source of the blast was a barrel containing chemical liquid that exploded owing to the negligence of workers.
"It is not an act of terror. The worker tried to cut the drum to use it as a trash can. Unfortunately, some chemical liquid was still left behind in the drum," he said, adding that the fire sparks emanating from the welding process triggered the explosion.
Jafar remarked that the explosion occurred at a construction site across the South Jakarta Court.
"(The blast took place) at a construction site where drums containing chemical liquid were left behind. It would be dangerous when ignited by fire," he revealed.
No casualties were reported in the incident, but the police have temporarily closed public access to Ampera Street.
Abdurahman was named a suspect in a series of bomb attacks, including at Thamrin Street, Jakarta, in a church in Samarinda and Kampung Melayu in Jakarta.
He was accused of masterminding the terror attacks.
Abdurahman was due to be freed on August 17, 2017, after serving a nine-year jail sentence, for his involvement in the military training of Jamaah Islamiyah in the Jalin mountains, Aceh Besar District, in 2010.
However, on August 18, 2017, the police had named him a suspect in the bomb attack on Thamrin street, Jakarta.
He was charged with Law No. 15 of 2003 on anti-terrorism.
Reported by Anita Permata Dewi