Islamabad, April 21: Pakistan Monday successfully test-fired its longest-range surface-to-surface ballistic missile for the second time in three days.

The test validated the operational readiness of a strategic missile group equipped with Hatf-VI (Shaheen-2) missiles, which can carry both nuclear and conventional warheads up to a distance of 2,000 km, the military added.

The launch conducted at an undisclosed location by the army's Strategic Force Command "marked the culmination of a field-training exercise," a defence statement said.

The launch was witnessed by naval chief Admiral Muhammad Afzal Tahir and other senior military officers, scientists and engineers of strategic organizations, the statement said.

Pakistan's missile development programme is aimed mainly at what it calls maintaining strategic balance with its nuclear-armed rival India.

The previous test launch of the Shaheen-2 was carried out Saturday.