A day after Temple Ner Tamid in Bloomfield was attacked in the middle of the night by a man who flung a Molotov cocktail at the synagogue’s main entrance, the Bloomfield Police Department and the Essex County Sheriff’s Office announced they are offering a $10,000 reward for information leading to the arrest of the person responsible.

Surveillance video of the attack shows the suspect, first approaching the building as if to size up his target before retreating several yards. Methodically, using a lighter, he ignites the fuse. Only after throwing the device do his movements speed up, as he sprints out of camera view.

The weapon did not explode and the bottle, police said, shattered without puncturing the glass doors. With no one in the building during the early morning hours, there were no injuries, police said.

The Bloomfield Police Department has asked anyone with information about the attack, which unfolded Sunday morning, Jan. 29, shortly before 3:30 a.m., to contact the department’s front desk or to use the Bloomfield Tip411 app. All calls will be kept confidential, the police said.

Coping with the aftermath of the attack, the synagogue reopened its doors on Monday after canceling all of its Sunday activities. Preschool classes went on as scheduled, and parents and staff were buoyed by one another even as they were shaken.

Then on Monday evening, in a step toward healing, the temple held a gathering both spiritual and pragmatic. Those who were there, including Montclair Third Ward Councilor Lori Price Abrams, a congregation member, said the sanctuary was overflowing from the bima past the back of the room. They discussed security issues, and also sang and prayed. Many like Price Abrams have seen their children grow up at the synagogue, and there was a pervasive sense that something hallowed had been altered in their lives with the attack.

“It was a violation of our home,” she said after the event. “That’s the feeling. it was someone who wanted to do harm to our home, our sacred space.”

Another member of the synagogue, Oliver Clayman, said he came to synagogue Monday night in part to make a statement that “we are not scared.”

“The community is together because it’s the togetherness that actually is the greatest weapon against the ignorance and the stupidity and the cowardice that was evidenced here last night.”

Josh Katz, the congregation president, said that in the temple’s offices during the day Monday, he reminded the staff that the synagogue has for years been proactive in enhancing security.

“We have people who pay attention and are there to protect us,” he said. “It’s not just a person standing there with the word security on their jacket carrying a gun that’s responsible for our safety. We have a very vigilant staff and a vigilant team of teachers and congregants. We’ve made security a priority.”

Meanwhile, clergy and others in the area said they felt deep kinship with Ner Tamid, a solidarity born out of shared experience.

“This impacts not just the Jewish Community but all of us as an attack on one of us is an attack on all of us,” the Montclair NAACP and Montclair Civil Rights Commission said in a joint statement. The organizations said they had reached out to the temple to offer support and to local leaders and elected officials “on how we can work together to fight hate against all our brothers and sisters.”

Though the synagogue escaped any damage and the suspect’s apparent intentions were thwarted when the Molotov cocktail did not explode, there was a recognition a day after, that the result could have been far worse.

“This incident has obviously shaken the community,” said Oren Segal, vice president of the Anti-Defamation League’s Center on Extremism and a Montclair resident. “It has also added to the fear and anxiety many in the Jewish community around the country are feeling in relation to the general uptick in antisemitism we have been documenting. That said, the leadership of Temple Ner Tamid was prepared, acted quickly and continue to provide a degree of comfort to all those who been affected.”

Wayne Richardson, the president of the Essex County Board of County Commissioners, said: “Acts of violence against any individual or group can’t be tolerated. If we are silent about a Molotov cocktail today, what will tomorrow bring?”

The attack, at 3:19 a.m., was captured by four surveillance cameras, positioned at different angles along the building. In the videos, the man, his face almost completely obscured by a ski mask, approaches the temple at 936 Broad St., walking unhurried along a long sloping driveway to the left side of the building. While there is a front door facing the street, the main entrance is near the back of the building adjacent to a parking lot.

The video was released by the Bloomfield Police Department on Facebook, but then later pulled from the site.

A joint investigation into the Sunday morning incident is underway by Bloomfield detectives, the Essex County Prosecutor’s Office, the FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives, the Bloomfield police said. The office of state Attorney General Matthew Platkin said it, too, was joining other agencies in investigating the attack.

After watching the video, Katz, the congregation president, who in part of his professional life is a corporate security consultant, called the man’s act “deliberate.”

“There’s no version of this where you say to yourself, well, this person was just playing a prank,” he said. “He has a mask pulled all the way down. This is a person who knew he would be noticed on a camera. There’s nothing about this that feels spur of the moment.”

Katz reflected on what he depicted as a difficult truth.

“I wish I didn’t have to say this,” he said, “but this is little bit of reality of Jewish life in America right now.”

The attack was discovered by the synagogue’s staff and security personnel when they came to work Sunday morning. Coming two days after Holocaust Remembrance Day, it evoked for many in the area the emotions that were stirred by a recent spate of violence, including the deadly shooting outside an East Jerusalem synagogue, the mass killings in Los Angeles and the fatal beating of a man by police officers in Memphis, Tennessee.

“While I have certainly been hearing from congregants who are concerned and angry,” said Bnai Keshet Rabbi Elliott Tepperman, “the most common response I have heard is one of resilience and solidarity.”

At the Monday night event, the congregation was led in song by the temple’s cantor, Meredith Greenberg, and by Peri Smilow, a singer and songwriter of Jewish music and a member of the congregation. As one, Price Abrams said, the congregants sang, Kol Ha’Olam Kulo, a song with words meaning, “the whole entire world is a very narrow bridge and the main thing is to have no fear at all.”

On Thursday night, Feb. 2, the synagogue is planning to hold another event, this time for the entire community, another opportunity, congregants said, for people to gather and lean on one another for support.