Troubling video has emerged of a previously unreported attack on an Orthodox Jewish man who was bashed with a chair and punched by a group of assailants in Brooklyn — just one amid a spate of 10 recent reported anti-Semitic attacks on city streets.

The victim had previously been too discouraged to report the Dec. 24 crime to cops, an activist told The Post.

He felt that there would be no point, the activist said, given new bail reform legislation that bars judges from detaining suspects in assaults that don’t result in injury — even in the case of hate crimes.

The attack unfolded at Albany Avenue and Lincoln Place in Crown Heights at about 6 p.m. on Dec. 24, the third night of Hanukkah, police said.

The same group of toughs are wanted for pummeling another Orthodox Jewish man on nearby Union Street about 30 minutes before, police said.

In that attack, one of the suspects punched the 56-year-old Jewish man in the back of the head before they ran off.

Troubling surveillance video of the unprovoked attack on Albany Avenue was tweeted on Monday by Yaacov Behrman, the founder of the Jewish Future Alliance.

“I found disturbing footage of chair throwing & assault on Chassidic Jew,” wrote Behrman of the incident, noting that it unfolded at Albany Avenue and Lincoln Place in Crown Heights on Dec. 24, the third night of Hanukkah.

The footage shows one among a group of about seven creeps throwing a chair at a lone Jewish man, then continuing on their way before wheeling around to chase him down, with one of the attackers punching the victim.

“It was traumatic, what happened to him,” Behrman told The Post of the victim, with whom he says he has spoken.

Behrman said that victim reluctantly discussed the harrowing encounter with him after being prodded by his roommate, but refused to go to the police for fear that they couldn’t protect him from reprisal in light of a package of sweeping criminal-justice reforms.

“He believes the justice system is so messed up he is not putting his name on file,” said Behrman of the victim, whose name he declined to share. “What do you tell someone like that?

“Chances are his fears are legitimate because they are not going to hold the suspect.”

The victim is specifically concerned about new bail-reform laws, which prohibit bail from being set on most low-level crimes including misdemeanor assault, as well as changes to discovery laws, which could give the perpetrators access to identifying information about him, Behrman said.

Both laws technically hit the books on Wednesday, but city courts have begun abiding by new bail guidelines this month, as in the case of Brooklyn woman Tiffany Harris.

Harris allegedly slapped three Orthodox women in Crown Heights on Friday while yelling “F-U, Jews!”

She was released without bail on Saturday, only to allegedly punch another woman on Sunday — for which she was again cut loose on Monday.

Harris’ alleged crimes and the attack detailed by Behrman are among a slew of anti-Semitic attacks across the city during the eight-day Hanukkah celebration — a total that doesn’t include a machete-wielding madman’s rampage Saturday night in Monsey, NY that left five Hasidic men injured.

The NYPD Hate Crimes Unit is investigating the incident. The department is working with local community affairs members to encourage the victim to come forward, cops added.