Republican candidate Donald Trump has agreed to be interviewed by the Federal Bureau of Investigation (FBI) as part of its investigation into the assassination attempt against the former US President at his rally in Pennsylvania earlier this month. 


The investigating agency said it would be "a standard victim interview we do for any other victim of crime" while it did not give a date for the interview, reported BBC. 


"We want to get his perspective on what he observed," FBI Special Agent Kevin Rojek said.


Amid several pieces of evidence, the investigators are yet to ascertain the motive to explain why 20-year-old Thomas Matthew Crooks opened fire on July 13. 


As per the report, Crooks was spotted by a local Swat team more than 90 minutes before the shooting, much earlier than previously thought. 


On Monday, investigators at the FBI said they believed Crooks conducted "careful planning" ahead of the 13 July rally and made "significant efforts" to conceal his activities, the report added. 


The planning, which included the purchase of components for explosive devices, was conducted in a manner that would not "significantly raise the suspicions of his parents," Rojek said. 


Several probes have been launched into what went wrong in securing Butler Fair Show grounds on July 13 where the assassination attempt was made. 


Secret Service Director Kimberly Cheatle resigned following the incident admitting failures. 


The agency was in charge of security on the day of the shooting within a fenced area and local law enforcement was responsible for areas beyond that. 


At 16:19 local time, a sniper of the local police texted two of his colleagues who were on the second floor of a warehouse overlooking the site, telling them he was clocking off. 


While leaving the building, he saw a young man sitting at a picnic table and notified others, sending a text: "Someone followed our lead and snuck in and parked by our cars just so you know", as per the BBC report. 


Pictures of Crooks were shared on the group chat. About 20 minutes later, Crooks was shot dead by the Secret Service.