The objects, left behind in a bloody crime scene at a Brooklyn subway station on Tuesday morning, gave investigators some of their first clues as they tried to find out who opened fire on dozens of unsuspecting New Yorkers who went to school and went to work. .
Within hours, these discoveries led to a person of interest.  And on Wednesday, as more information was gathered, authorities named the man a suspect, urging the public to contact police if they saw him.
The suspected killer called himself and was arrested about an hour later, two law enforcement sources said.
Frank James, 62, has been charged in federal court with violating a law banning terrorist and other violent attacks on the public transportation system, a U.S. prosecutor has said.  James allegedly shot at least 33 times, hitting 10 people, authorities said.  The motive is still unknown, officials said.  CNN contacted James’s federal lawyer for comment.
See how authorities gathered information to identify the suspected perpetrator – and what led to his arrest.


KEYS, A CARD, A JACKET AND A WEAPON 
Credit card investigators at the scene offered a key piece of the puzzle they had undertaken to solve.
The card was used to rent a U-Haul truck that authorities believed was linked to the shooting, two law enforcement sources said.  NYPD internal emails aired on CNN on Tuesday did not say how authorities thought the van was connected.  In the emails, top executives shared a stock image of a white U-Haul truck and asked officers to be on alert for a similar vehicle with an Arizona license plate.
The truck was spotted in Brooklyn on Tuesday, police officials told CNN.
It was about three blocks from Kings Highway Station, where the video showed the suspect entering the subway on Tuesday morning, before the shooting, said NYPD chief of staff James Essig.
“The key to this truck was found at the crime scene,” Essig told a news conference Wednesday.  The U-Haul records showed that James rented the van on Monday afternoon, according to a criminal complaint.  Surveillance footage showed a man wearing a “yellow hard hat, orange work jacket … holding a backpack in his right hand and dragging a bag in his left hand” leaving the vehicle on foot early Tuesday morning in the West. 7th Street and Kings Highway in Brooklyn, according to the complaint.
No weapons or explosives were found in the van, police officials said Wednesday.  The vehicle had food debris and it appeared that James may have been sleeping in it, sources said.  A license plate reader spotted the truck moving over the Verrazzano Bridge in Brooklyn, Staten Island, around 4 a.m. Tuesday, law enforcement officials said.
A black cart with which the suspect was seen on video was also found at the crime scene, Essig said.  The same was true of the orange jacket, he added.  A construction helmet the suspect was seen wearing was found in a rubbish bin, Essig said.
The shootings took place around 8:24 a.m., officials said.
Authorities also found a 9mm Glock pistol, three rounds of ammunition, two incendiary smoke grenades, two unexploded ordnance and an ax, Essig said on Tuesday.  Two officials said they believed the gun was blocked during the shooting.
The gun had scratch marks and prosecutors said they believed it was an attempt to “falsify the serial number”, according to court documents.  Bought by James in Ohio in 2011, Essig said.
By Tuesday night, authorities had compiled a rough description of what happened to the subway train earlier that day: After boarding train N – which starts at Kings Highway – the suspect opened two canisters “spreading smoke” across the subway, “said NYPD Commissioner Keechant Sewell on Tuesday night.
He then allegedly shot several people as the train entered the 36th Street subway station in Sunset Park, Sewell said.  Witness footage shows the chaos and panic of those moments: A video shows smoke billowing from the car where the shootings took place as screams were heard, while another showed people running outside the subway train.
After allegedly opening fire on the train, the suspect boarded an R train and went to the 25th Street stop, Essig told a news conference Wednesday.
Less than an hour later, around 9:15 a.m., he was spotted boarding the subway at 7th Avenue and 9th Street at nearby Park Slope, Essig added.


THE AUTHORITIES EXECUTED SEARCH ORDERS 
When the NYPD posted a message on Twitter Wednesday morning asking for information on James’ whereabouts, they included a snapshot of one of the many YouTube videos the suspect linked to.
The videos discussed violence, mass shootings and mental health, often in an adventurous way, and provide information about a journey James embarked on before the attack.
Many of the videos uploaded by James included references to the violence, including a group of people he thought had abused him, in addition to broad social and racial groups he seemed to hate.
In a video released in February, he criticized a plan by New York Mayor Eric Adams’s administration to address security and homelessness in the subway system, in part through the increased presence of mental health personnel, saying the effort was “doomed”. to fail”.  He described his own negative experience with urban health workers during a “mental health crisis back in the ’90s and’ 80s and ’70s.”
In a video uploaded last month, James spoke of post-traumatic stress and said he left Milwaukee, Wisconsin on March 20 and embarked on a journey east, saying he was heading to the “danger zone”.  Preliminary information showed that James mentioned the homelessness, New York and its mayor in online posts, Sewell said on Tuesday.
Videos show he arrived in Philadelphia around March 25 after several stops.
Federal prosecutors believe James visited a warehouse in Philadelphia that was full of ammunition and more weapons the night before the attack, according to court documents.  A proof associated with the installation was found on the jacket found at the scene of the shooting.
Authorities issued a warrant for a search of the facility on Tuesday and found ammunition and a “pistol barrel that allows a silencer or suppressor to be installed,” among other things, according to the complaint.
Authorities also conducted a search warrant for an apartment in Philadelphia that they believe James rented for just over two weeks, starting around March 28, and found “an empty magazine for a Glock pistol, a teaser, a large rifle case. and a blue smoke pot.  “said the complaint.


JAMES CALLED A SELF-ADVICE, SOURCES SAY 
James was taken into custody about 30 hours after the shooting.  He called Crime Stoppers on Wednesday and said he actually saw his face on the news and knew he was wanted, two law enforcement sources told CNN.
He said he was at a McDonald’s in Manhattan’s Lower East Side, sources said.  He told the operator he would be inside the restaurant to charge his phone, a senior law enforcement source said.  A few minutes later, the call rang.
But another call was made to 911 by a man who believed he had located James, one of the two sources told CNN.
Patrol officers arrived at McDonald’s and were able to locate James under the block shortly after a passerby pointed at him, a senior law enforcement source said.
Investigators are now examining the camera’s plans to try to establish a timeline for the whereabouts of the suspected perpetrator since he was last found in Park Slope on Tuesday and when he was arrested Wednesday, a senior law enforcement source told CNN. .
The investigation is ongoing, officials said.