The Indonesian police said Monday that the National Police’s counterterrorism squad known as Densus 88 has arrested 13 suspected terrorists in the country’s province of Riau.

Details of the arrested people hasn’t been issued. The National Police’s spokesperson Ahmad Ramadhan said that the special unit is still investigating the case.

Police operation against terrorism has been running for several years in Riau.

In August last year, five suspected terrorists were arrested in the Kampar district of the province. Densus 88 uncovered a training site for terrorists in the same district in November 2019.