ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF INJURY OR DEATH A man holds an injured outside a hospital after a blast in Kabul, Afghanistan May 31, 2017.REUTERS/Mohammad Ismail

Image used for illustrative purposes. Damaged cars are seen after a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Omar Sobhani

Damaged cars are seen after a blast at the site of the incident in Kabul, Afghanistan May 31, 2017.REUTERS/Omar Sobhani

Afghan officials inspect outside the German embassy after a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Mohammad Ismail

ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF INJURY OR DEATH Injured Afghans run from the site of a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Omar Sobhani TEMPLATE OUT

ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF INJURY OR DEATH Injured Afghans run from the site of a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Omar Sobhani

Damaged cars are seen at the site of a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Omar Sobhani

Afghan men carry an injured man after a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Omar Sobhani

ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF INJURY OR DEATH An Injured Afghan man walks on the street near a hospital after a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Omar Sobhani

Burned vehicles are seen after a blast at the site of the incident in Kabul, Afghanistan May 31, 2017. REUTERS/Omar Sobhani

Relatives of victims listen to hospital officials after a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Mohammad Ismail

Afghan municipality workers sweep a road outside the German embassy after a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Mohammad Ismail

ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF INJURY OR DEATH A woman sits outside a hospital after a blast in Kabul, Afghanistan May 31, 2017.REUTERS/Mohammad Ismail

ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF INJURY OR DEATH Afghan security forces carry injured men in the back of police car near the site a blast in Kabul, Afghanistan, May 31, 2017. REUTERS/Omar Sobhani TEMPLATE OUT

ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF INJURY OR DEATH A wounded man lies on the ground at the site of a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Omar Sobhani

An Afghan man reacts at the site of a blast in Kabul, Afghanistan May 31, 2017.REUTERS/Omar Sobhani

Relatives of Afghan victims mourn outside a hospital after a blast in Kabul, Afghanistan May 31, 2017. REUTERS/Omar Sobhani