New York straphangers were keeping their eyes peeled for potential “copycats” Thursday, telling The Post they remained on high alert — even after subway shooting suspect Frank James was nabbed over his alleged bloody Brooklyn attack.

The 62-year-old’s arrest on Wednesday after a 30-hour citywide manhunt did little to alleviate the fears of those riding the subway, with several saying they still don’t feel safe.

“I’m on very high alert,” said Damara Hall, 25, who rides the 2, 4 and 5 lines to work in Manhattan. “I don’t feel safer even [after] they caught the guy. I don’t think anyone should live in fear but it’s hard not to nowadays.”

Hall was among those concerned that others may try to imitate Tuesday’s attack that left 29 injured when James allegedly opened fire on an N train at Sunset Park during morning rush hour.

“I think there are more people who are going to try this. You see somebody do that and he was able to get away. Somebody could be watching this and say, ‘I can do that.’ That worries me,” Hall said.

Peterene Williams, who takes the E train from Brooklyn to Manhattan for work, said: “Now they caught him, but I have to look out for others, like copycats.”

“I think it’s going to set a precedent for others to do the same thing because they realize how long it takes to be caught. He got off the train and walked away,” Riya U, an 18-year-old college student armed with pepper spray, told The Post at Penn Station.

Police said James boarded the train with a black cart, set off a gas cylinder and fired 33 rounds at passengers — striking 10 and injuring 19 others — as they pulled into the 36th Street station just before 8:30 a.m.

He fled on an R train to the next stop at 25th Street and remained on the run until he was taken into custody in the East Village on Wednesday afternoon after he — and other vigilant New Yorkers — called Crime Stoppers.

The attack made several commuters rethink how they ride the subway, with some saying they would be more vigilant and aware of those around them going forward.

“I’m scared because I take the train every day to work,” said Tsomo, a 62-year-old nanny who was clutching her Buddhist prayer beads at Times Square station.

“I look around me. I look at everyone — who is where, who has what. If I don’t feel safe, I’ll change my seat or I don’t feel safe in that car, I’ll go to next one.”

Waleska Menscia, 47, who lives close to the 36th Street station where the attack occurred, said: “I sit where they have the three seats that are sideways so I can look in all directions. I can see what’s going on. That’s my new thing now.”

She added: “Now when I see people with big bags, I worry — what’s in there?”

Linda Moreno, 30, who takes the N and D from Brooklyn to work in Manhattan, said she was relieved James was off the streets.

“It does make me feel a little safer but it doesn’t take the edge off because catching one guy doesn’t mean we are solving the problem,” she said.