Ainsley Earhardt reported from Fort Hood, Texas, this morning as investigators focus their attention on a possible verbal altercation between the gunman and at least one other soldier.

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Lt. Gen. Mark Milley told reporters at Fort Hood that there's a "strong possibility" that words were exchanged between Army Spc. Ivan Lopez.and another soldier or group of soldiers right before the shooting.

Lopez, who was being treated for depression, anxiety and sleep disorders, killed three people and wounded 16 before fatally shooting himself on Wednesday.

Earhardt reported that four people who were wounded in the attack remain hospitalized in serious condition. Three had been in critical condition before being upgraded to "serious."

Meantime, attention is also being focused on a Facebook page that apparently belonged to the shooter. Lopez is believed to have been using the name Ivan Slipknot.

On March 1, a post on the page read the following:

"I have just lost my inner peace, full of hatred, I think this time the devil will take me. I was robbed last night and I am sure it was 2 guys. Green light and finger ready. As easy as that."

UPDATE, 4:00 p.m. ET: Lopez's father released a statement that reads: "This situation is very painful. I ask for prayers for all the families affected (…) My son could not have been in his right mind, he was not like this."

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