30 April 2018 12:19 pm
The blasts went off during rush hour on Monday morning in the Shash Darak area of the Afghan capital.
In the first explosion, a suicide bomber detonated himself close to the National Directorate of Security (NDS), the main Afghan intelligence agency, TOLO News quoted an interior ministry spokesman as saying.
A second explosion followed 20 minutes later as emergency medical workers and journalists had arrived at the scene, the report said.
A spokesperson for the Afghan health ministry said the attacks killed at least 21 people and wounded 27 others.
Al Jazeera's Jennifer Glasse, reporting from Kabul, said six journalists who rushed to cover the aftermath of the first explosion were killed in the second blast.
AFP news agency reported that its chief photographer in Kabul, Shah Marai, was among the fatalities.
An Al Jazeera photographer was also injured in the incident.
TOLO News also reported that two other journalists were wounded in the second blast.
There were fears that the death toll could rise.
It was still unclear if the second explosion was also caused by a suicide bomber.
"It's a very grim morning here," Al Jazeera's Glasse said describing the situation in the Afghan capital.