A suicide car bombing and clashes with Taliban insurgents across Afghanistan have killed at least 25 security personnel.
The violence comes as the United Nations urges parties to the Afghan conflict to cease hostilities during the Islamic holy month of Ramadan, beginning this week.
Local television stations quoted security officials in the embattled Helmand province as saying that a suicide bomber Thursday afternoon rammed his explosives-laden car into an office of the Afghan intelligence agency.
Initial reports said at least six people were killed and several more wounded. The district chief of the National Directorate of Security (NDS), Tor Jan, was said to be among the dead.
The Taliban claimed credit for the violence, with a spokesman saying the massive explosion destroyed the facility in the Washir district and killed at least 20 people, including Jan.
The Islamist insurgency often releases inflated tolls for such attacks. Helmand is the largest Afghan province and is mostly controlled by, or under the influence of, the Taliban.
Meanwhile, officials in neighboring Kandahar province have confirmed that a Taliban ambush Wednesday night left at least 13 Afghan soldiers dead and eight others wounded.
Defense Ministry spokesman Dawlat Waziri said in Kabul that dozens of insurgents participated in the deadly assault that targeted an Afghan military base in the Maiwand district. He added that Afghan forces drove the assailants back, killing about 20 of them.
This was the second insurgent attack on a military installation this week in Kandahar.
Taliban fighters on Monday night staged a surprise assault on several security outposts in the Shahwali Kot district, killing at least 20 Afghan soldiers and wounding 15 others.
On Wednesday, the Taliban also assaulted security outposts in western Badghis province, killing at least six Afghan forces and wounding several others.
The increase in the number of casualties among Afghan security forces has been a cause of serious concern for the government and its international partners.
The head of the U.N. Assistance Mission in Afghanistan, or UNAMA, has appealed for a cessation in hostilities during Ramadan.
"In the same spirit, I would like to call parties to the conflict to respect this religious obligation and halt the fighting," said Tadamichi Yamamoto.
Also Thursday, officials in the northern Afghan city of Kunduz reported that a Taliban rocket attack in the early morning hit a school in the provincial capital, killing at least one student and wounding nine others.
The deaths come as Afghan civilian casualties already have risen to record levels in the first four months of 2017, according to UNAMA.