On 13 October 2023, NBC News reported that Israeli first responders had recovered from the bodies of Hamas militants a range of documents. One of these documents (pictured below) appears to have relayed an order to massacre.
I have translated the relevant portion of the document as follows:
It is interesting that this document has flown under the radar. Assuming its authenticity, it corroborates an order to massacre by Hamas.
It is considered another Israeli fake. Perfectly clean Word document that speaks of targeting schools but they attacked on a Saturday and holiday when schools were closed. Other points were noted when the NBC report came out. It's also not how Hamas actually behaved inside Israel.