At least three policemen were killed in a firing incident which took place Friday afternoon in Pakistan's southwest city of Quetta, reported local media Express.

According to the report, the firing incident took place when two unknown gunmen riding a motorcycle opened fire at the police on a checkpost at the Sariab Road near a stadium in the downtown area of Quetta.

The assailants fled the scene after killing the police. No group has claimed the responsibility for the attack.

The incident is one of the most serious terrorist attacks that has happened in the country over the last couple of weeks.

Since the monsoon rains and flood hit Pakistan at the end-July, there were not many terrorist attacks reported in the country. The target killings which broke out in Pakistan's southern port city of Karachi at the beginning of this months are rather related to partisan struggles than to terrorism. During the week-long unrest in Karachi, over 100 people were reportedly killed.