Chief of the public relations division at the East Java Provincial Police, Senior Commissioner Gatot Repli Handoko, confirmed the arrests.
"It is true that Densus 88 at the National Police Headquarters has arrested several suspected terrorists in East Java, including Surabaya, Sidoarjo, Mojokerto, and Malang," he said.
However, he refused to divulge the exact number of terrorists who were arrested.
As of Friday night, Densus 88 was still developing the investigation in the case.
Handoko said the provincial police have not received technical directions as to whether the suspected terrorists will be taken to Jakarta for further investigation.
Earlier, Densus 88 had arrested a suspected terrorist, identified by his initials as AIH, from a house in Medokan Sawah No. 121, Rungkut, Surabaya.
During the search, the Densus 88 team also seized arrows, samurai, boxing, and taekwondo equipment as evidence.
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