I just noticed that the link you provided says nothing about the officers/officers being hit by friendly fire. I don't doubt it... but would love to read the "other" side of the story if there is one somewhere....
I haven't seen an official source that says this either, but fratricide does appear to be a possibility based on the information available, or lack of information. They do appear to be trying to saddle responsibility for the injuries and death on Stewart, whose house was raided, but haven't come out and said specifically that Stewart shot any of the 6 cops which is unusual, especially after all this time. Most of the accounts of Francom's death state that he was shot during the raid, not that Stewart shot him.
You would think that the doctors had recovered at least on bullet from the 6 officers that were shot and could match it to Stewart's gun, but after 4 months, not such claims are being made by the cops.
Here is a vid from one of the responders. It has graphic language, so not work or family friendly. The second link provides more information and validates the first link as being from the incident.
There seems to have been quite a few shots gapped over a long period of time.
As an aside, note the officer shot in the hip who fell down the stairs to the basement and then ran back upstairs. Obviously, the shot to the hip did not take him out of the battle or stop his mobility.