ISLAMABAD, Jan. 21 (Xinhua) -- At least 18 people were killed and nearly 50 others injured when a bomb went off inside a vegetable market in Pakistan's northwest tribal area of Kurram Agency on Saturday morning, local Urdu media reported.

Dunya News reported that the blast happened at the time when dozens of people were busy shopping in the vegetable market located in Parachinar area of Kurram Agency, a semi-autonomous tribal region along Pakistan-Afghanistan border.

Nature of the blast has not been officially confirmed yet, but some media reports said that the explosion was carried out by a remote controlled device.

The injured people were shifted to a nearby hospital where several of them are said to be in critical condition.

Security forces cordoned off the area for investigations.

No group has claimed responsibility for the attack yet.