"As a citizen of Indonesia, Im giving a personal appearance to the KPK summons for questioning in a case," Jero said upon arriving at KPK office at 19.45 a.m. on Thursday.
However, Jero refused to talk about the corruption and extortion allegations against him.
"Later, after the questioning, I will explain it to you," Jero told newsmen at KPK office.
Thursdays questioning came after the KPK named Jero a suspect on September 3, 2014.
The anti-graft commission has named Jero Wacik, a former energy and mineral resources minister and senior member of President Susilo Bambang Yudhoyonos Democrat Party, in an extortion case in which he allegedly amassed Rp9.9 billion during his ministerial term 2011-12.
According to the investigation of the anti-graft body, Jero ordered his staff to generate additional funds to meet his operational costs.
Jeros staff then carried out bogus activities and managed to find several sponsors.
Jero allegedly extorted money from various parties by citing that the operational budget set aside for energy and mineral resources minister for the 2011-13 period was less than the allocation during the 2004-2011 period, when he was the minister for tourism and creative energy.
Earlier, on Wednesday, the KPK questioned Deputy Minister for Tourism and Creative Economy Sapta Nirwandar, who is a witness in the case.
"I am here not as a witness but as a discussion partner to KPK investigators," remarked Sapta, who admitted that he was questioned about the standard operational money given to ministers.