Condemning the attack against the Afghan Attorney General's lawyers working to facilitate prisoner releases, US Special Representative for Afghanistan Reconciliation Zalmay Khalilzad has called for a full investigation into the attack.

In a tweet today, the representative said US calls for a full investigation to find the perpetrators and bring them to justice. "This attack underscores what we all know: Spoilers (both domestic and foreign) are trying to disrupt and delay," he tweeted.

Zalmay who led negotiations with the Taliban ahead of a deal signed in February between the US and the Taliban, urged both sides to reach intra-Afghan negotiations.

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"Both sides should not be deterred, and push forward to take the steps necessary to reach intra-Afghan negotiations, where a comprehensive ceasefire and a political settlement can be negotiated as quickly as possible. This is what the Afghan people want and we stand with them," he said.

On Monday, gunmen shot dead two prosecutors and three other employees of the attorney general's office.