India, Sept. 25 -- The gunman who fired upon a Dallas immigration field office, killing one detainee and critically wounding two others before taking his own life, did multiple searches of ballistics and the "Charlie Kirk Shot Video" between September 23 and September 24 and left a warning for ICE agents in a handwritten note, the FBI has said.

The shooter fired upon a Dallas immigration field office from a nearby roof on Wednesday morning. All three victims were in a transport van outside the facility at the time the firing took place.

While the identity of the shooter has not been disclosed publicly, a law enforcement official told AP, on condition of anonymity, that he has been identified as 29-year-old Joshua Jahn.

In an update on ...