KOCHI: The recently launched state-of-the-art underwater harbour defence system of Navy has detected a boat that was 'inadvertently' straying into the security cauldron put in place at the high security naval zone here on the eve of Independence Day.

The unlit 'vallam' (country boat) approaching the Naval area in the Ernakulam Channel was detected by the Integrated Underwater Harbour Defence and Surveillance System (IUHDSS), set up here to track and warn surface and underwater threats.

"A prompt action by the duty Naval patrol boat in the Ernakulam channel resulted in prevention of infringement of the security cauldron being put in place around the naval area due to heightened security state," the Navy said in a release today.

The new automatic system, first of its kind in the country, was installed at the harbour here a fortnight ago as part of Navy's initiatives to beef up coastal security.

It is capable of detecting, identifying, tracking and generating warning for all types of surface and underwater threats. The Navy release said the panic stricken boat crew failed to stop when asked by the duty patrol boat to do so for verifying documents and continued rowing towards the Naval area.

Seeing the patrol boat closing on them, one of the crew members jumped into the water and in the commotion the country boat toppled.

Both the crew were subsequently rescued by the Naval personnel and handed over to the police.

The "vallam" was detained by the Naval police and has been released after due investigation, Navy said.