Samira Muhammadi hopes an international investigation can "extinguish" her pain after a Pakistani bombing killed her son and hundreds of other Afghans in the capital Kabul last month.

Also Read | India terms Pakistan’s bombing of drug rehab centre in Kabul a ‘barbaric’ act

The March 16 attack hit a drug treatment centre and killed 411 people, according to Afghan officials.

A United Nations source, speaking to AFP on condition of anonymity, said they had verified at least 250 killed, with more still missing.

Editorial | ​No end to suffering: On the Pakistan-Afghanistan conflict