ISLAMABAD, March 20 (Xinhua) -- At least six security personnel were killed when unknown militants opened fire at a security check post in Pakistan's southwest Balochistan province on Wednesday, local reports and officials said.

Ziarat Deputy Commissioner Qadir Bakhsh Parkani said the attackers sprayed bullets indiscriminately on the security forces' check post in Ziarat, adding the terrorists fled the scene after carrying out the attack.

Following the incident, heavy contingent of police and rescue teams reached the area and shifted the bodies to a nearby hospital for medico-legal formalities.

Police cordoned off the area and kicked off a search operation to apprehend the on-the-run militants.

No group or person has claimed responsibility for the attack yet.