Amnesty International has urged European nations to stop sending Afghans who do not qualify for asylum back to their "deeply unsafe" home country.
The human rights group says the policy risks causing serious harm to those affected.
Amnesty's call comes after a steady rise in violence over recent years as the Taliban gained ground across the country.
Cities, including the capital Kabul, have been hit by a wave of suicide attacks.
"Amnesty International is calling on all European countries to implement a moratorium on returns to Afghanistan until they can take place in safety and dignity," the group said in a report issued today.
It says no part of the country can be considered safe.
The report follows a sharp increase in the number of Afghans returned from Europe, either as a result of forced deportation or "assisted voluntary return".
It said the total almost tripled from 3,290 to 9,460 between 2015 and 2016.
"In their determination to increase the number of deportations, European governments are implementing a policy that is reckless and unlawful," said Anna Shea, Amnesty International's Researcher on Refugee and Migrant Rights.
She said governments were being "wilfully blind" to evidence that violence was at a record high.
Afghans have been among the main groups of asylum seekers in Europe, with 108,455 first time asylum seekers registered in the EU in the 12 months to the end of June, second only to Syrians, according to EU statistics agency Eurostat.
European governments, faced by voters angry at hundreds of thousands of arrivals from the Middle East, Africa and South and Central Asia over recent years, have cracked down, pledging to send rejected asylum seekers back to their home countries.
The policy has proved particularly controversial in Afghanistan, where many European governments say that despite widespread violence, safety is sufficient to allow returns to some parts of the country.
According to United Nations figures, at least 1,662 civilians were killed and 3,581 wounded in the first half of the year, with nearly 20% of civilian casualties coming in Kabul itself.
"Afghanistan is deeply unsafe, and has become more so in recent years. Yet European countries are returning people to Afghanistan in increasingly large numbers, even as the violence in the country escalates," the report said.