Khost, a restive Afghan province bordering Pakistan, is home to members of the Taliban and also Al Qaeda militants, officials say. No group has so far claimed responsibility for the attack.
A car bomb attack on an Afghan police special forces base followed by an ongoing gun battle have killed three policemen and wounded dozens of people.
Militants detonated the car bomb outside the gate of the base in the city of Khost near the Pakistan border early in the morning before trying to storm the compound, a security source said on Tuesday.
A gun battle between the attackers and security forces was ongoing, officials and an AFP correspondent reported.
Four attackers have been killed while two more were still fighting, Afghanistan's Interior Ministry spokesperson Tariq Arian told reporters.
The assault has so far left three policemen dead and wounded 33 people, including 11 civilians, Sakhi Sardar, a senior official at Khost hospital told AFP.
Three killed in separate attack
Three civilians were killed and 10 others were wounded in a separate attack on Tuesday when a "sticky bomb" attached to a car exploded near Kabul airport, police spokesperson Ferdaws Faramuz said in a statement.
Violence has surged across Afghanistan in recent weeks even as the Taliban and Afghan government remain engaged in peace talks to end the country's long-running conflict.
Afghan and US officials have repeatedly warned that the rising bloodshed was threatening the talks being held in Qatar since last month.
Concerns over civilian casualties
Parties must not let levels of violence & harm to civilians return to previous highs. #Afghanistan’s civilians need protecting & if parties do that it can also be a fillip for #Afghanistan peace talks. Read report https://t.co/gty1OVvvpH pic.twitter.com/aBSq5dPH4Z— UNAMA News (@UNAMAnews) October 27, 2020
The United Nations Assistance Mission in Afghanistan (UNAMA) said in a report released on Tuesday that the number of civilians killed and wounded has failed to slow since the start of peace talks on September 12.
"The peace talks will need some time to help deliver peace," UNAMA chief Deborah Lyons said in the report.
"But all parties can immediately prioritise discussions and take urgent, and frankly overdue, additional steps to stem the terrible harm to civilians."
At a time when Afghans should feel hopeful, the horrific rise in violence, particularly in the last few weeks, erodes this spirit. Those responsible for the violence need to know that neither the Afghans nor their regional and international partners will let hope fade. https://t.co/pHA2mb79aX— Deborah Lyons (@DeborahLyonsUN) October 25, 2020
UNAMA, however, said that the overall civilian casualty figure had dropped by around 30 percent in the first nine months of 2020 compared to the corresponding period last year.
The first nine months of this year saw 2,177 civilians killed and 3,822 wounded, the report said.
The majority of the civilian casualties, about 58 percent, were caused by "anti-government elements" like the Taliban and Daesh, it said.
Afghan security forces were responsible for 23 percent of all civilian casualties, many killed in air strikes and ground engagements.
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