ISLAMABAD, Feb. 28 (Xinhua) -- At least four security personnel were killed and six others injured in a suicide attack in Pakistan's southwest city of Quetta on Wednesday evening, local media reported.

Local Urdu channel Samaa TV quoted security sources as saying that a suicide bomber attacked the personnel present at a camp of Frontier Corps, a paramilitary force, in Nauhisar area located at the outskirts of Quetta, the provincial capital of Southwest Balochistan province.

Additional contingents of security forces and rescue teams rushed to the site and shifted the bodies and injured to the Combined Military Hospital in the district.

The death toll might further rise as some of the injured are in critical condition. Earlier reports said the attack took place in Khooni Talaab area.

According to the reports, heavy firing was also heard after the attack. Security forces have cordoned off the site and launched a search operation in the nearby areas to arrest the aids of the attacker.

No group has claimed the attack yet.

Earlier in the day, at least two policemen were shot dead in a targetted attack at the convoy of a deputy superintendent of police in Quetta city.