KABUL, Jan. 4 -- At least 11 people were killed and 20 others injured in a suicide bomb attack in Microryan neighborhood of Afghanistan's capital of Kabul Thursday night, a health official said.

"A suicide bomb attack ripped through a road in Microryan, Police District 9, at around 08:45 p.m. local time," a security source told Xinhua.

"The incident occurred shortly after a demonstration ended in the area and those among the casualties were anti-riot police and civilians," the source said.

Earlier, a public health official told local media that 11 people, including five police personnel, were killed and 20 others injured after the explosion in the crowded area.

He said the number of casualties was likely to change as some injured were in critical condition.

Several shops and vehicles were also damaged after the blast in the area where dozens of five-story apartment buildings are located.

Security forces have cordoned off the area for precautionary measures.

Further details about the incident are still forthcoming amid the absence of any official statement.

No group has claimed responsibility for the attack yet.

Kabul with a population of nearly 5 million has been hit by series of terror attacks over the past couple of years.

On Dec. 25, a teenage suicide bomber killed seven people and injured six others in nearby fortified Shash Darak locality.