Twenty people have died after a truck packed with explosives was detonated by Taliban militants outside a hospital in southern Afghanistan.
Many of the victims in the attack in Qalat city were doctors and patients, according to local media reports.
Later, officials said another 16 people, many of them civilians, had been killed in a US air strike aimed at Islamic State militants in the east.
Last month, at least 473 civilians were killed in the conflict, the BBC found.
Civilians made up a fifth of all known casualties during the month of August, our research revealed.
What happened in the hospital bombing?
A senior defence ministry official in the capital told Reuters news agency the "huge" bomb had been carried by a "mini-truck" before it was detonated near the hospital in Qalat.
It was the main health facility in Zabul province, according to reports. Governor Rahmatullah Yarmal said it had been "destroyed".
The Taliban have said they were targeting government intelligence offices, next door to the hospital.
The final death toll from Thursday morning's attack is still unclear. Zabul's deputy governor said 20 were confirmed dead, with some 90 injured.
People at the scene described seeing women and children pulled from the rubble.
"It was horrific," university student Atif Baloch said, according to news agency AFP.
Ambulances have been ferrying casualties to hospital in the neighbouring province of Kandahar.
What happened in the air strike?
The Afghan defence ministry says an attack took place on Wednesday night in Khogyani district in Nangarhar province which was aimed at Islamic State fighters, according to Reuters news agency.
But a Nangarhar security official confirmed to the BBC that 15 civilians had been killed and six others wounded in the strike.
According to reports, those killed had been working in a pine nut field.
"The workers had lit a bonfire and were sitting together when a drone targeted them," tribal elder Malik Rahat Gul told Reuters.
An investigation into the incident is being carried out.
What is the security situation in Afghanistan?
The Afghan conflict continues to be one of the deadliest in the world. The BBC found an average of 74 people were killed every day throughout August.
Hopes had risen that the 18-year conflict could be coming to an end after it was revealed the Taliban and US had almost reached a peace deal in early September.
But US President Donald Trump pulled out of the agreement after a Taliban attack in Kabul killed a US soldier and 11 others on 6 September.
The Taliban have continued to carry out near daily attacks since then, with national elections due at the end of the month. On Tuesday, the group targeted an election rally where President Ashraf Ghani had been due to speak, leaving 26 people dead.
However, despite the Taliban attacks hitting the headlines, United Nations statistics have shown more civilians were killed by Afghan and US forces in the first half of 2019 than by insurgents.