The death toll from a bombing at a Shiite shrine in south-west Pakistan has increased to 24 after four victims died in hospital, police said.

A suicide bomber struck the shrine packed with worshippers in a remote village in Jhal Magsi district, about 240 miles east of Quetta in Baluchistan province, on Thursday.

Senior police officer Mohammad Iqbal said on Saturday that more than 20 victims were still being treated, some with critical wounds.

The Islamic State group claimed the attack. IS has claimed several past attacks in Baluchistan, which has been the scene of a low-level insurgency by Baluch nationalists and separatists demanding more autonomy and a greater share in the region's natural resources of oil and gas.

The bomber detonated his explosives vest when he was stopped for a routine search by a police officer guarding the shrine.

Five children, a woman and two police officers were among those killed.

Sunni extremists and IS perceive minority Shiites as apostates and have carried out many such attacks across the country.

At least 75 Shiites were killed in twin bombings at a market in Parachinar in the country's north west In June. Lashkar-e-Jhangvi, a sectarian Sunni extremist group, claimed responsibility.

In February, an IS suicide bomber struck inside a famed Sufi shrine in southern Sindh province, killing 88 worshippers.