Hidden Chinese vessel spotted 120 NM from Indian waters in Bay of Bengal

French firm Unseenlabs used radio frequency satellite surveillance to trace the covert Chinese vessel, which allegedly switched off its AIS near Indian maritime zones

A ‘hidden’ Chinese research vessel operating in the Bay of Bengal was flagged by French maritime intelligence firm Unseenlabs earlier this week, raising concerns over Beijing’s growing maritime footprint in the region.

 

Unseenlabs, which specialises in radio frequency (RF) satellite surveillance, tracked the vessel during a 16-day monitoring mission. The ship reportedly switched off its Automatic Identification System (AIS)—a common method of evading detection—while conducting suspected underwater reconnaissance.

 

“While not broadcasting AIS, its RF signature was consistent and traceable, enabling our systems to monitor its movement over several days,” the firm stated in its report. “We suspect that this prominent Chinese research vessel was likely operating with strategic intent.”

 

 

Of the 1,897 ships monitored during the mission, nearly 10 per cent—including the Chinese vessel—were found operating without active AIS signals.

 

Possible underwater reconnaissance near Indian EEZ

Unseenlabs indicated that the vessel’s activities appeared to include seafloor mapping, acoustic surveys, and the identification of submarine transit corridors—typical tactics in anti-submarine warfare (ASW) and long-term maritime surveillance planning.

 

Although the ship stayed outside India’s territorial waters, it came within 120 nautical miles of sensitive maritime zones, prompting alerts from Indian defence authorities.

 

According to The Economic Times, the Indian Navy and Coast Guard are closely monitoring the situation, reviewing surveillance protocols, and may raise the matter diplomatically.

 

Series of past incidents involving Chinese vessels

The latest detection follows a pattern of Chinese vessel activity in the Indian Ocean Region (IOR):

 

March 2024: Xiang Yang Hong 01 was spotted off the eastern coast of India during an Agni-5 missile test.

 

July–August 2024: Xiang Yang Hong 03 was tracked near an Indian naval submarine warfare exercise.

 

March 2025: Xiang Yang Hong 01 returned to test high-endurance autonomous underwater vehicles (AUVs), anchoring for three months west of the Andaman Islands. China maintains that its vessel operations near Indian waters are research-driven and benign, including for civilian and military data collection on routes to the Maldives.

 

India reinforces maritime surveillance and deterrence

The Indian Navy remains watchful. Vice Admiral Rajesh Pendharkar, Eastern Naval Command chief, has previously confirmed that Chinese research ship movements are under strict observation to prevent territorial violations.

 

India is also accelerating investments in maritime surveillance infrastructure to ensure readiness against encroachments in strategic waters such as the Bay of Bengal.