Trump-Possible-Assassin was photographed by police minutes before the attack

His behavior was so strange and so different from that of the other participants in the demonstration that the local police noticed him, radioed their concerns and took a photo. But then he disappeared.

The image was broadcast by officers stationed outside the security perimeter that hot, sunny Saturday afternoon, but the man did not reappear until witnesses saw him climbing up the side of a squat factory building just 135 metres from the stage.

There, six minutes after Trump began his speech, he opened fire in an attempt to assassinate the likely Republican presidential candidate. The gunman killed one rally attendee and seriously injured two others. Trump suffered an ear injury but was unharmed and appeared at the Republican National Convention in Milwaukee just days later with a bandage over the wound.

Now come the questions, and there are many. Multiple investigations have been launched, both into the crime itself and how law enforcement allowed it to happen. It’s becoming increasingly clear that this was a complicated failure involving multiple missteps and at least nine local and federal law enforcement agencies that were supposed to be working together. Law enforcement has also warned of the possibility of copycat attacks and further violence.

This story is based on interviews with eight law enforcement officials and four people familiar with a law enforcement briefing given to senators on Wednesday, some of whom spoke to The Associated Press on condition of anonymity about the investigation into the Trump assassination.

Several agencies work together to secure events

Whenever a president, political candidate or other high-ranking official comes to town, the Secret Service always works with local law enforcement. And Saturday’s rally was no exception. An advance team arrives early to scout the scene and identify potential problem areas. They order vehicles to move away. They set up barriers. They close off streets.

In some larger cities, one or two local agencies are working alongside the federal teams. In more rural areas, a local agency does not have enough staff, so multiple agencies are often involved. On Saturday, members of at least six different agencies were involved in the show of force, including two sheriff’s offices, local police, state police, and several Secret Service teams, as well as fire and rescue teams. Within these agencies, there are individual departments with different tasks.

In theory, more staff would be better. But it can often lead to communication problems, and it is unclear how the information about 20-year-old Thomas Matthew Crooks was passed on. For example, it is not clear how widely his photo was circulated or whether everyone was equally aware of the potential threat.

All of the extra officers can be a drain on resources and overwhelm agencies. The Secret Service is constantly protecting the president, candidates and others, as well as handling major national security events. The same is true of local police, who told the Secret Service they do not have enough staff to station officers outside the building all day.

The Secret Service patrols the area inside the restricted area after people pass through the metal detectors. Local law enforcement is responsible for the area outside the restricted area.

Reports of someone on the roof

The gunman, later identified as Crooks, disappeared from the crowd of Trump supporters dressed in red, white and blue. The stream of supporters streaming through the metal detectors was slowing down. Trump prepared to move on.

The rooftop from which Crooks fired is located in a complex owned by AGR International Inc., a supplier of automation equipment to the glass and plastic packaging industries. The building was closed that day, except for police.

Crooks was spotted again when members of a local SWAT team stationed at the complex noticed him walking around and looking at the roof. One officer took a photo of Crooks and radioed the others to be on the lookout for a suspicious person looking through a rangefinder – a small device similar to binoculars that hunters use to measure the distance to a target.

Not long afterward, witnesses reported seeing him scale the building closest to the stage, then place his AR-style rifle on the roof, a detonator in his pocket, to detonate crude explosive devices he had hidden in his car parked nearby.

Outside, a local officer climbed onto the roof to investigate. The gunman turned and pointed his rifle at him. The officer didn’t fire a single shot – or couldn’t. Crooks did, however, and fired into the crowd toward the former president. Panicked spectators then ran for cover while Secret Service agents shielded Trump and pulled him off the stage. Two sniper teams were stationed on buildings behind Trump, and the team farther away from Crooks fired once, killing him.

In the congressional briefing on Wednesday, FBI and Secret Service officials laid out a clearer timeline: Crooks was identified as a potential threat a full hour before the shooting, they saw him using the rangefinder about 40 minutes before the shooting, and then saw him looking through the rangefinder again about 20 minutes before the shooting.

Many investigations, few answers

“We are talking about a failure,” Homeland Security Secretary Alejandro Mayorkas told CNN. “We will conduct an independent investigation to analyze how this happened, why it happened, and make recommendations and findings to ensure this does not happen again.”

Republicans on the House Oversight Committee have subpoenaed Secret Service Director Kim Cheatle. House Speaker Mike Johnson said he would set up a task force to investigate the incident, and some Republicans called for Cheatle to resign.

Cheatle himself said in an interview with ABC News that the shooting was “unacceptable.” “And something like this should not happen again.”

Security measures for Trump and President Joe Biden were increased, and independent presidential candidate Robert F. Kennedy Jr. also received security personnel.

Biden has ordered an independent investigation into the shooting. The Inspector General of the Department of Homeland Security has also launched an investigation into the Secret Service’s handling of the shooting.

But it’s a big job. Special agents, presidential protection teams, counter-assault and sniper teams were on site that day. There were also about 50 firefighters and emergency personnel on site, along with dozens of Butler Township Police officers, Beaver County and Butler County deputies, and Pennsylvania State Police patrol officers.

It will take weeks, if not months, to interview all the officials involved and determine exactly how Crooks was able to carry out the most serious assassination attempt on a president or presidential candidate since the assassination of Ronald Reagan in 1981.

The shooter had prepared for the bloodbath. Investigators found that he had several loaded magazines with him. He also bought 50 bullets on the day of the shooting. His father had purchased the rifle legally years earlier.

Investigators found a bulletproof vest in his car and another explosive device in his home, where he had received several packages in recent months, including some containing potentially dangerous materials. The FBI gained access to Crooks’ cellphone, searched his computer, home and car, and has interviewed more than 100 people so far.

But much of his communication was through encrypted messages. Investigators reviewed more than 14,000 images on his cellphone and found that Crooks had also searched online for information about the bullet’s trajectory.

But the investigation has so far failed to solve the mystery of the biggest question: Why did he do it?