JAKARTA (THE JAKARTA POST/ASIA NEWS NETWORK) - The anti-terror squad of the Indonesian national police has captured another terrorist suspect, bringing to four the total number of alleged terrorists detained since Wednesday (June 8).

"His initial is S. He has been detained yesterday," National Police chief spokesperson Sr. Comr. Agus Rianto said on Friday (June 10) regarding the latest arrest, which occurred in the Kenjeran area of Surabaya.

On Wednesday, police in Surabaya arrested three terrorism suspects by the initials of PHP, BRN and FN. PHP is reportedly a former drug convict released in 2014.

No evidence was secured during the arrest of S, but police believed S was involved in the same network as the three suspects detained earlier, Agus added.

The four were part of a new network affiliated and in ongoing contact with the Islamic State in Iraq and Syria (ISIS), Agus claimed.

"They are involved with people in Syria; they communicate with the IS spokesperson," Agus said, adding that they were members of a network called Sibghatullah.

The four are suspected of planning to carry out terrorist attacks during Ramadhan, said Agus, adding that documents and information had been found on the planned attack.