PESHAWAR: Four people were killed including a soldier and two paramilitary troops when a bomb concealed in a plastic bag went off in Pakistan's northwestern tribal area near the Afghan border, officials said Saturday.

The incident occurred in the Khyber district when security officials spotted a suspicious plastic bag near a security checkpoint.

"As the security officials were inspecting the plastic bag, the bomb concealed in it went off, killing a solider, two paramilitary troops and a civilian," a local administration official told AFP, requesting anonymity.

The incident was confirmed by other local security officials.

There was no immediate claim of responsibility.— AFP