Civilian casualties in Afghanistan reached a record high in the first half of 2016, the UN has said, with children in particular paying a heavy price as insurgent groups stepped up fighting.

Between January and June, 1,601 civilians were killed and 3,565 were wounded – a 4% increase in casualties compared to the same period last year, the UN assistance mission in Afghanistan (UNAMA) said on Monday.

The casualties have reached their highest level since the UN began issuing its authoritative reports in 2009, and include 1,509 children – a figure the UN described as “alarming and shameful”.

The statistics are a grim indicator of growing insecurity in Afghanistan as the Taliban step up their nationwide insurgency and Islamic State seeks to expand its foothold in the east of the country.

“Every single casualty documented in this report – people killed while praying, working, studying, fetching water, recovering in hospitals – every civilian casualty represents a failure of commitment and should be a call to action for parties to the conflict to take meaningful steps to reduce civilians’ suffering,” UNAMA’s chief, Tadamichi Yamamoto, said.

“Platitudes not backed by meaningful action ring hollow over time. History and the collective memory of the Afghan people will judge leaders of all parties to this conflict by their actual conduct.”

The report comes after the deadliest attack in 15 years in Kabul killed 80 people and left hundreds maimed, in an assault claimed by Isis.