QUETTA: At least four people were killed Tuesday when a suicide bomber rammed an explosive-laden vehicle into an Afghan security checkpost near the Pakistan-Afghanistan border-crossing at Chaman, Afghan police said.

The explosion occurred near Wesh Mandi area on the Afghan side of the border, injuring over a dozen other people, Afghan police officials said.

“The strength of the blast smashed window panes and glasses of nearby shops and houses,” said a low-level Afghan official, who requested not to be named.

Security was beefed up and the border crossing was shut down for all kinds of traffic following the incident.

“We have tightened security following the suicide attack on the Afrghan side,” an officer of the Frontier Corps, also requesting anonymity as he was not authorised to speak to the media.

Home secretary Balochistan Asad Gilani earlier told Dawn.com that security forces and law enforcement agencies in Balochistan have been placed on high alert prior to the start of the holy month of Muharram and following the killing of Tehrik-i-Taliban Pakistan (TTP) chief Hakimullah Mehsud in a US drone strike.