Three calls were detected from the thick forests in these regions between May 23-29, according to the sources.
Two calls were tracked in places near Mangaluru in Dakshina Kannada district, Chikkamagalur and Uttara Kannada jungles by the Central intelligence agencies.
The sleuths of State Internal Security Division (ISD) visited the spot and have launched a probe.
Preliminary findings have suggested that the satellite phone calls were made from four locations in 10 days. The agencies are tracking down the persons who used the banned satellite phones.
Sources explained that this is the third time that satellite phones were being used in this year in the coastal and Malnad regions.
The Central agencies have been alerting the state police department on these developments.
This time satellite phone signals originated from the forest that falls between Yallapur and Sirsi towns in Uttara Kannada; Natekal, Kulai regions in the outskirts of Mangaluru city; and the jungles between Kadur-Birur towns in Chikkamaglur, the sources said
Earlier, the phone calls were tracked to Mudibidre, Mudipu regions in Dakshina Kannada; in dense forest regions of Uttara Kannada; and another two locations from Chikkamagalur.
Since terror activities targeting civilians were being reported from Jammu and Kashmir, Central agencies have told their counterparts and authorities in Karnataka to be vigilant about the developments.
Central agencies have gathered information about suspected anti-national activities taking place in the coastal districts of Dakshina Kannada, Uttara Kannada and Udupi; and Chikkamaglur and Shivamogga districts in the Malnad region.
The issue of the use banned satellite phones was raised in the state Assembly session last year and Home Minister Araga Jnanendra had given detailed statements that the government is handling the situation in coordination with Central agencies, including the Intelligence Bureau (IB) and Research and Analysis Wing (R&AW).
Intelligence agencies suspect and track whether the anti-national forces are activating sleeper cells in the state.
The phone calls are being made despite intelligence agencies being on alert in the state.
Jnanendra had stated on the floor of the House that there were 256 instances of satellite phone usage in 2020 and 220 in 2021, which were tracked to foreign locations.
After the 26/11 Mumbai attacks, using satellite phones was banned by the Directorate General of Shipping.