Jakarta Blasts: Was It a Terrorist Act? Probe on School Explosions Underway

Two blasts on a school campus in Indonesia's capital injured at least 20 people on Friday, said authorities, who reported the cause was under investigation.

The explosions occurred at around 12:15 pm (0515 GMT) around a mosque on a high school campus in North Jakarta, said deputy coordinating minister of politics and security Lodewijk Freidrich Paulus.

He urged the public to not rush to judgement as information emerged over what happened and why.

"Don't jump to the conclusion that this is a terrorist act," Lodewijk said as quoted by Antara state news agency, adding that the probe was ongoing.

He said the explosions happened at the back of the mosque and near its door.

Jakarta police chief Asep Edi Suheri offered differing details earlier Friday, saying there was an explosion "in the vicinity" of a high school in the sprawling city.

"The initial data we have received indicates that there are approximately 54 individuals affected," Asep told reporters in comments broadcast by Kompas TV.

"Some have minor injuries, some moderate, and some have already been discharged."

Lodewijk gave a lower toll of at least 20 people injured from the incident, with three victims suffering from heavy injuries.

Authorities cordoned off the area and "were processing the crime scene", Asep said, including a bomb squad from Jakarta police as they tried to determine the cause.

Asep said authorities had also set up posts in two hospitals to assist relatives in finding injured victims.

"We are still investigating, as this incident just occurred," Asep said.