The attack struck near the private Shinozada hospital in the capital's Macrorayan neighborhood, the sound of the powerful blast roaring throughout the capital.
The bombing killed at least nine Afghan civilians and one foreigner and wounded 60, said Wahidullah Mayar, a Health Ministry spokesman. U.S. Col. Brian Tribus, a NATO spokesman, said the three contractors had been killed, without elaborating.
Conflicting information is common after such attacks.
