» UPDATE: Prosecutors on Oct. 21 said evidence refutes claim that passengers may have filmed the rape of a woman on a SEPTA commuter train instead of calling police. Read more.

The rape of a passenger on a SEPTA train one night last week lasted about six minutes, and other passengers not only looked on but appeared to point their smartphones at the assault as it happened, police said Monday.

But the only person to call 911 during the attack was an off-duty SEPTA employee, whose quick thinking allowed Transit Police officers to arrive three minutes later, interrupt the assault, and arrest the alleged rapist, newly filed records show.

“We want everyone to be angry, disgusted, and to join us in being resolute in keeping our system safe,” Transit Police Chief Thomas Nestel III said Monday at a news conference. “We need the public to notify us when they see something that seems to be unusual.”

» READ MORE: SEPTA passengers won’t be charged for failing to intervene in a rape on the train, prosecutors say

The man charged in the attack, Fiston Ngoy, told police that he recognized the woman on the train and approached her to start a conversation and that their encounter was consensual. She told police that account was completely false, according to the affidavit of probable cause for his arrest.

Investigators say that the victim was alone when Ngoy, 35, sat down next to her in the railcar Wednesday night and that he ignored her pleas to go away. That account, along with the violent attack that followed, was corroborated by SEPTA surveillance footage, the affidavit said.

Ngoy remained in custody Monday in lieu of $18,000 bail, awaiting an Oct. 25 preliminary hearing in Upper Darby.

The assault took place just before 10 p.m. Wednesday as the train on the Market-Frankford Line headed west toward Upper Darby. It was unclear Monday how crowded the train was at the time, but Upper Darby Police Superintendent Timothy Bernhardt said that had bystanders intervened, the victim may have been spared from the attack.

» READ MORE: Tips for how and when to intervene if you witness an emergency like last week’s rape on SEPTA

“There was a lot of people, in my opinion, that should have intervened. Somebody should have done something,” Bernhardt said Saturday. “It speaks to where we are in society and who would allow something like that to take place. So it’s troubling.”

Nestel echoed those sentiments Monday, adding that his officers need riders to partner with them during crises.

“Riders don’t always know when to contact the police,” he said. “I’m here to tell you that when you see inappropriate behavior, behavior you wouldn’t want your 10-year-old to see, call 911.”

The alleged victim told police she remembered getting on the train and then nothing until the officers pulled her assailant off her.

She told police that she had a few beers after work, but had gotten on the wrong train. Investigators determined she boarded the subway car at 9:15 p.m. at the Frankford Transportation Center in Northeast Philadelphia, according to the affidavit.

About a minute later, Ngoy entered the train, the affidavit said. He began to talk to her shortly after that, moving to the seat next to her. She repeatedly pushed Ngoy away, as he attempted to touch her and at one point grabbed her breast, the video showed.

“Throughout this time, the victim is obviously struggling with keeping him off of her,” investigators wrote in the affidavit.

At 9:52, Ngoy raped the woman, and was pulled off of her by responding SEPTA Transit Police officers after the train pulled into the 69th Street stop in Upper Darby, according to the affidavit.

Ngoy later told police that he had seen the woman before and then struck up a conversation with the woman on the train that escalated into kissing and physical contact, the affidavit said. He claimed that she initiated the sexual encounter and never resisted his advances.

The victim, in a statement given to police at Delaware County Memorial Hospital, said she had never seen Ngoy before, and never gave him permission to touch her.

Ngoy faces charges of rape, involuntary deviate sexual intercourse, sexual assault, and related offenses. There was no indication Monday he had an attorney.

He listed Broad Street Ministry — an outreach center in Center City — as his last known address. A spokesperson for the organization said she could not comment Monday on whether Ngoy received services at the ministry.