A young Israeli man who also holds U.S. citizenship was arrested in Israel on March 23, in connection with a wave of threats made to Jewish community centers in the U.S. and several other countries in past months, according to the FBI and local authorities. (Jenny Starrs/The Washington Post)

Police say vandals attacked a Jewish cemetery in Northeast Philadelphia this weekend, just a week after a similar incident was reported at a Jewish burial ground in suburban St. Louis.

According to Jim McReynolds, a detective for the Philadelphia Police Department, at least 75 to 100 headstones at Mount Carmel Cemetery were discovered knocked over Sunday morning. Several of the headstones were broken. Police are investigating the incident as a case of vandalism.

“It’s pretty much intentional,” McReynolds told The Washington Post. “We just have to find out if it’s drunken kids or an act of — well, it is a predominantly Jewish cemetery, so we have to look into that fact.”

In a statement released Sunday evening, the police department said that it appears the headstones were knocked over sometime after dark on Saturday. Police don’t have surveillance footage of the attack or any leads as to who might have committed it. The Anti-Defamation League is offering a reward of $10,000 for information leading to the arrest of the perpetrators.

Aaron Mallin of northern New Jersey told local news channel ABC6 that he went to Mount Carmel to visit his father’s grave Sunday morning and discovered the damage.

“It’s just very disheartening that such a thing would take place,” Mallin said.

It is not clear whether the attack was motivated by anti-Semitism. McReynolds said there have been no such reports of vandalism at Jewish cemeteries in the region, though 33 tombstones were found toppled earlier this month at Holy Redeemer Cemetery, a Catholic burial ground about two miles from Mount Carmel.

In January, someone threw rocks through eight windows at a Philadelphia synagogue, Temple Menorah Keneseth Chai, before services were about to start. A window at the temple also was broken in December. At the time, police said that the incidents were connected but that they did not consider them a hate crime, according to ABC6.

The vandalism at Mount Carmel comes after a similar attack at Chesed Shel Emeth Cemetery in University City, Mo., where as many as 200 headstones were toppled. That incident, along with bomb threats against dozens of Jewish community centers across the country, sparked anxiety among many U.S. Jews.

“Attacking a cemetery, especially one that is all-Jewish, all-Catholic, or whatever it is, is basically an attack on the culture, the identity of the people that cemetery represents,” Aaron Breitbart, a researcher at the Simon Wiesenthal Center in Los Angeles, told The Post after the St. Louis incident.

On Tuesday, after facing pressure to condemn the vandalism in St. Louis, President Trump called anti-Semitism “horrible” and vowed to take steps to counter extremism.

Two Muslim American activists started a fundraiser to help pay for repairs at Chesed Shel Emeth Cemetery. More than $130,000 had been donated in less than a week. On Sunday afternoon, the organizers of the campaign posted an update saying they had contacted Mount Carmel to offer funds from the campaign.

The incident in Philadelphia also brought a wave of condemnations online, including tweets from Rep. Robert A. Brady (D-Pa.), who represents Philadelphia; Emmanuel Nahshon, a spokesperson for the Israeli Foreign Ministry; and the Anti-Defamation League.

The Anne Frank Center also tweeted a statement calling on Trump to give a nationally televised speech condemning anti-Semitism and other forms of religious discrimination.