A blast rocked the central Damascus district of Marjeh on Tuesday, Syrian state television said, with a watchdog group saying at least nine people were killed in the attack.
"Terrorist explosion in Marjeh district of Damascus and preliminary information on casualties," state television reported.
"The toll in a car bomb near the old interior ministry building Marjeh district rose to nine and the number was expected to rise further because there are dozens of injured, some in critical condition," the Syrian Observatory for Human Rights watchdog said.
An AFP correspondent reported that automatic weapons fire rattled the district immediately after the blast.
Footage broadcast on state television showed smoke billowing over the site of the explosion, which blew out the windows of surrounding cars, knocking the bumpers off some and starting fires.
Uniformed and armed plainclothes security forces could be seen running near the scene, as residents fled from the site.
Several mutilated bodies could be seen lying in the street, and at least one body wrapped in a white sheet was laid out alongside an ambulance.
Fire engines were at the scene with firefighters battling several blazes.
The attack came a day after the blast in the Mazzeh neighbourhood of the capital targeting Prime Minister Wael al-Halqi.
The car bomb, which exploded as his convoy passed through the upscale neighbourhood, killed one of his bodyguards and five other people, according to the Observatory.
Damascus has seen a wave of major bombings in recent weeks, including on April 9, when a massive blast in the centre of the city killed at least 15 people.