Jakarta – In a strange turn of events, the Indonesian Air Force has said the rumbling noises that rattled Jakarta over the weekend originated from a ceremony held at Halim Perdanakusuma Air Base in East Jakarta.
Air Force spokesperson First Marshal Fajar Adriyanto said the event, which was held to welcome new recruits, featured a series of ceremonial gestures, including the ignition of the highly-explosive substance trinitrotoluene (TNT).
Halim Perdanakusuma Air Base base spokesperson Maj. Rizwar confirmed that TNT had indeed been exploded twice on the site at 7:30 p.m. on Sunday evening and at 5 a.m. on Monday morning.
He claimed the explosions were part of the Air Force's tradition and that the resulting rumble was simply a "sound effect" of the ceremony.
"[...] the rumbling was only a sound effect; it was not destructive," Rizwar said on Monday as quoted by kompas.com.
Previously, social media users in Jakarta reported hearing two loud rumbles of unknown origin on Sunday evening. Some claimed that the sound – described as resembling distant thunder – was significant enough to have rattled objects in their homes.
Prior to the Air Force's statement, the Meteorology, Climatology and Geophysics Agency (BMKG) assumed that the sound was likely produced by thunder over Mount Salak in Bogor, West Java.
"The result of the BMKG's inspection using lightning detectors shows a number of lightning-related activities around Mount Salak between 7 p.m. and 9 p.m.," BMKG tsunami and earthquake mitigation head Daryono told kompas.com on Sunday.
He said the noise was not produced by seismic activity, adding that it was possible that similar sounds would be heard in the future. (rfa)