Inside an NYPD car at the 34th Precinct was 21-year-old Rigoberto Lopez. He was delivered to a suspect lineup and then to central booking.
Lopez, who is believed to be homeless, was charged Sunday afternoon with murder and attempted murder, CBS2's Dave Carlin reported.
Police said an officer who had seen a suspect image from surveillance video recognized Lopez wearing blood-stained clothing and was walking on Autoban Avenue in Washington Heights on Saturday night. Officers said on him they found a knife.
All of the victims were homeless and the attacks unprovoked, police said.
The first attack happened Friday morning at the 181st Street stop. A 67-year-old man who uses a walker to get around was stabbed and survived.
Twelve hours later, a 40-year-old man was found dead inside a train at the far end of the line in Far Rockaway.
Less than two hours later at the 207th Street stop, 44-year-old Claudine Roberts was stabbed and killed.
The fourth victim is a 43-year-old man who survived after being stabbed, back at the 181st Street station.
Taking extra precautions because of COVID-19 concerns, Winston Roberts spoke with CBS2's Hazel Sanchez through an open window at his Crown Heights, Brooklyn home. He said the arrest of the man police say killed his daughter, Claudine Roberts, brings him little comfort.
"They catch him, but that still don't remedy the situation," Winston Roberts said. "They're going to have them in the jail eight to 10 years and then back on the street so he can do somebody else something."
The NYPD added 500 uniformed officers to patrol the city. The extra officers are seen as crucial, but some said it must be a first step of many.
"We will immediately commence a surge of officers to patrol both above and below ground," NYPD Commissioner Dermot Shea said Saturday.
Politicians and and union leaders gathered Sunday in Brooklyn to demand better policing, mental health services and affordable housing.
City Council Majority Leader Laurie Cumbo said she, too, was attacked by someone else on the subway Friday and help was hard to find.
"I ran to the police van, to run and to ask for help. And when I got to the police van, the police officers inside said, 'We are not police officers. We are traffic safety. We cannot get out of the van,'" Cumbo said.
Claudine Roberts' father said the changes will come too late for his daughter.
"That's how life goes. That's how life goes," Winston Roberts said.
Some are also pushing for the reopening of 24-hour subway service.
"Let's get more cops in the subway system and crime will go down and we need another agency down here to take care of these people who have a mental health issues," said Earl Phillips, secretary and treasurer of Transport Workers Union Local 100.
Police said Lopez has prior arrests, some for violent offenses and that he has a history of mental illness and was hospitalized for it at least twice. He was awaiting his arraignment on Sunday evening.
Local elected officials are holding a vigil on Monday at the 207th Street station in Inwood at 3 p.m. to remember the lives lost.
CBS2's Hazel Sanchez and Christina Fan contributed to this report.
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