Updated

A bomb blast killed at least two people and wounded six others Sunday in Pakistan's troubled southwestern city of Quetta, police said.

The bomb, which was planted on a busy road, went off at around sunset when people were returning from work.

"The bomb had been planted between two vehicles parked along the Sariab road. We can confirm the deaths of two people and wounds to six others as a result of this explosion," Muhammad Babar, a local police official, told AFP.

Babar said police were investigating the incident and the blast site had been cordoned off.

Quetta is the capital of Baluchistan, a vast, sparsely-populated southwestern province believed to have substantial oil and gas reserves.

The city has been the focus of a surge in sectarian violence, mostly targeting the Shiite Muslim minority who make up around a fifth of Pakistan's mainly Sunni Muslim population.

The province also suffers from Islamist violence and a decade-long separatist insurgency by Baluch nationalists who want greater autonomy and a larger share of oil and gas revenues.