Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: Kabul, Afghanistan (CNN) After months of delays, Afghan government negotiators signed a peace deal Thursday with an insurgent faction led by one of the country's most notorious warlords. The deal was signed at a ceremony attended by negotiators, the President's national security adviser, and representatives of the Hezb-i-Islami faction of Gulbuddin Hekmatyar. Afghan and US officials applauded the agreement, but a prominent human rights organization strongly criticized the deal. In a statement, the US Embassy called Thursday's accord "a step in bringing the conflict in Afghanistan to a peaceful end." That sentiment was echoed by Afghanistan's chief executive -- who is in a shaky power-sharing agreement with the country's President.Human Rights Watch says deal compounds "culture of impunity"Gulbuddin Hekmatyar had a ruthless reputation 
 Question:During the subsequent civil war between rival mujaheddin commanders in the 1990s, _ was accused of committing atrocities against civilians during the deadly struggle for control of the Afghan capital.

Gulbuddin Hekmatyar