There has been a 39% rise in violent incidents in Afghanistan so far this year compared with the same period last year, a UN report says.
In the past three months alone, there have been 7,000 violent incidents in the country, says the report by Secretary General Ban Ki-moon.
The violence mainly involves gunfights and attacks using improvised bombs.
The report said most of the incidents were in the south and south-east, many of them near to Kandahar city.
The BBC's Paul Wood in Kabul says the document does not make comforting reading for Nato or the Afghan government.
He says the figures seem to suggest that Taliban attacks are falling in places where Nato is bolstering its numbers, but violence and insecurity is spreading to other parts of the country.
The report says the average monthly rate of violent incidents for the year is 2,108 and details figures for violent incidents in June (2,626), July (2,605) and August (2,306).
Mr Ban, who presented the quarterly update to the Security Council, blames most of the violence on insurgents.
"The increase can be attributed, in the context of overall intensified fighting, mainly to the use by anti-government elements of landmine-like pressure-plate improvised explosive devices and suicide attacks, in violation of international humanitarian law," says Mr Ban's report.
Over June, July and August, the number of civilians killed or injured in attacks rose by 5% compared with the same quarter last year.
The secretary general said at least 77% of those casualties were caused by the government's enemies.
His report also says there was an increase in the number of so-called complex attacks, where a group of suicide bombers and gunmen assault a high-profile building.
Kabul has seen several of those recently including those targeting the US embassy and the British Council.
The secretary general also notes what he calls a disturbing trend towards attacking targets such as hospitals or mosques.
For example, more than 30 civilians were killed in an attack on a hospital in the province of Logar in July.