The Afghan Health Ministry says at least 11 people were killed and 25 injured when a suicide bomber blew himself up in Kabul as security personnel were conducting an operation at the scene before the attack.
"We can confirm that so far 11 bodies have been brought to our hospitals as well as 25 wounded," the AFP news agency quoted Health Ministry spokesman Wahid Majroh as saying on January 4.
The spokesman cautioned that the toll could rise.
AFP quoted a security source as saying 20 people had been killed in the attack, which occurred about 8:30 p.m. local time.
Witnesses told RFE/RL that the blast could be heard throughout the capital.
Kabul police spokesman Basir Mujahid said police were conducting operations against illegal drug and alcohol sales in the area and that security personnel were attempting to maintain safety among crowds that had gathered.
"Kabul police forces were there to prevent a possible protest when a suicide bomber approached them and detonated his suicide vest," Mujahid said.
Tolo News reported that local residents had participated in a street demonstration in the area earlier in the day.
There was no immediate claim of responsibility.
Kabul has been hit hard by terror attacks attributed to Taliban, Islamic State (IS), and other militants operating in the country.
On December 29, Afghan authorities said at least 41 people were killed and 84 wounded by multiple bomb blasts at a Shi'ite cultural center in Kabul.
IS claimed responsibility for the December 28 attack, which Afghan President Ashraf Ghani called a "crime against humanity" committed by terrorists.
The Sunni extremist group has recently increased its attacks against Shi'a in Afghanistan -- particularly in Kabul.
U.S. forces led an invasion to drive Taliban extremists from power after Al-Qaeda militants whose leaders were sheltering in Afghanistan carried out the September 11, 2001, attacks on the United States.
U.S. troops have remained in the country, although at greatly reduced numbers, helping to train and support Afghan forces in their battles against the militant groups.