Islamabad, Dec 2 (IANS): At least 12 people were killed and six others injured in three separate incidents of firing, bomb explosion and clash between security forces and militants in Pakistan Tuesday, media and officials said.

Two people were injured when a bomb exploded near the convoy of a senior official in Quetta, the capital city of the country's southwest Balochistan province, Xinhua reported.

Police said Raza Mohammed Barrech, the education adviser to the chief minister of Balochistan, narrowly survived the explosion which was carried out by a remote controlled device.

In another incident in Quetta, four personnel of the paramilitary force Frontier Corps were injured when some unidentified gunmen opened fire at them.

Those injured were shifted to a nearby hospital.

In another incident in the country's northwestern tribal area of Orakzai Agency, 12 militants were killed in a clash with security forces.

Dawn TV said that the militants attacked a security checkpost located in Shirin Darra area of Orakzai Agency, a restive tribal area on the Pakistan-Afghanistan border.

The forces repelled the attack, killing 12 militants and injuring several others.

The remaining attackers fled the scene, leaving the bodies of their accomplices behind.

No group has claimed responsibility for any of the three attacks yet.