India has successfully tested its nuclear-capable K-4 submarine-launched ballistic missile (SLBM) from the nuclear-powered submarine INS Arighaat, defence sources told India Today TV. 

The missile, with an estimated strike range of 3,500 kilometres, was launched in the Bay of Bengal off the coast of Visakhapatnam under the operational control of the Strategic Forces Command.

This marks the second test of the K-4 missile following the first launch from INS Arighaat last year, bringing the system closer to full operational readiness. 

Developed by the Defence Research and Development Organisation (DRDO), the solid-fuel K-4 missile is intended to equip India’s nuclear-powered submarines, significantly enhancing the Navy’s second-strike capabilities and reinforcing the country’s nuclear deterrence.

INS Arighaat, commissioned in August 2024, displaces 6,000 tonnes and represents India’s latest addition to its nuclear-powered submarine fleet. 

The vessel can carry K-4 missiles with a 3,500-kilometre range, marking a substantial upgrade over the K-15 missiles on the first nuclear-powered submarine, INS Arihant, commissioned in 2016, which had a limited range of 750 kilometres.

Earlier K-4 tests had been carried out from submersible pontoons; however, launches from INS Arighaat signal a significant step towards the missile’s operational deployment.

While the Defence Ministry has not issued an official statement regarding the test, analysts note that the K-4 programme is a critical component of India’s effort to match global strategic capabilities. Countries such as the United States, Russia, and China already deploy SLBMs with ranges exceeding 5,000 kilometres.

The successful test underscores India’s continued focus on strengthening its strategic deterrence and modernising its nuclear triad.