No ideology identified so far, says FBI
Bernd Debusmann Jr
Reporting from Bethel Park, Pennsylvania
The FBI and US Department of Justice - including Attorney General Merrick Garland and FBI Director Christopher Wray - are currently briefing reporters, although they are limited in what they can say amid the ongoing investigation.
FBI Special Agent Kevin Rojek said that it appears the "shooter acted alone" and that there are no ongoing security concerns.
"We have not identified an ideology associated with the subject," he said, warning that the investigation is still in its early stages.
Evidence response teams are still processing the crime scene in Butler, he said, adding that agents are still combing through the suspect's social media and online presence for clues.
The gun, he confirmed, was an AR-style rifle purchased legally. A suspicious device found in the suspect's car is still being examined.
Another FBI official said the incident is also being investigated as a potential act of domestic terrorism.
Bernd Debusmann Jr
Reporting from Bethel Park, Pennsylvania
The FBI and US Department of Justice - including Attorney General Merrick Garland and FBI Director Christopher Wray - are currently briefing reporters, although they are limited in what they can say amid the ongoing investigation.
FBI Special Agent Kevin Rojek said that it appears the "shooter acted alone" and that there are no ongoing security concerns.
"We have not identified an ideology associated with the subject," he said, warning that the investigation is still in its early stages.
Evidence response teams are still processing the crime scene in Butler, he said, adding that agents are still combing through the suspect's social media and online presence for clues.
The gun, he confirmed, was an AR-style rifle purchased legally. A suspicious device found in the suspect's car is still being examined.
Another FBI official said the incident is also being investigated as a potential act of domestic terrorism.
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www.bbc.co.uk