CHRISTCHURCH, New Zealand — The city has been here before, but never like this.

Eight years ago, when it last experienced mass trauma, Christchurch was told it was experiencing its darkest hour. Back then, it seemed impossible, with 185 dead and vast property damage from a massive earthquake, to imagine anything darker.

But then came Friday, when a 28-year-old Australian extremist allegedly drove with guns — first to one mosque, then across the city to another — to unleash slaughter on a community just as it came together to pray. The shooting left 49 dead and 39 hospitalized; 11 of them are in intensive care. Had the police not apprehended the suspect just over a half-hour after the attack was launched, further carnage may well have been inflicted.

“The earthquakes were natural disasters. This is man-made,” said a woman dispensing free tea, coffee and biscuits on Saturday outside a Salvation Army church down the road from the second mosque, where seven people were killed. She had pies heating in the oven for passersby.

The urge to give and receive comfort is the same as last time, but the source of the anguish this time is not comparable.

People drifted past alone or in small groups. Many had flowers to place outside a police cordon blocking traffic around the crime scene. The blockade was a delicate flutter of plastic tape, a police car and two policemen bearing — unusually in this country — guns.

Christchurch residents know from that earlier darkest day the value of small gestures: hot food from a stranger, a smile of solidarity, a gentle word. They learned last time to be liberal with hugs, with friends as well as with people they barely knew. They are hugging again.

The city was quiet the day after the massacre. Many shops remained closed. Hagley Park, the green lungs of the city, would on a normal fall Saturday be a kaleidoscope of kids and adults playing sports, runners, walkers and people whizzing by on electric scooters. It has been mostly empty since schools and clubs suspended activities out of concern for security and respect for the dead.

The mosque on Deans Avenue, the gunman’s first target, sits opposite the park, guarded from public view by more plastic tape and four or five armed constables. Pedestrians flowed by in a light stream, pausing to stand in disbelief and shock, write on a giant plastic condolence sheet and lay flowers. No one spoke above a whisper.

Some have reached for normalcy as an expression of solidarity. At Scorpio Books, a much-loved 40-year-old institution in the city, store manager Kit Lyall put a chalkboard out front with a message in the language of New Zealand’s first people, the Maori: “Kia kaha Ōtautahi,” which means, “Stay strong, Christchurch.”

The store is collecting contributions to help the victims and their families and has set up a display of books that might help ease the city’s sadness.

In the hours after the massacre, Lyall and her staff shielded children who had been ordered to leave the 2,000-strong school strike demanding action to combat climate change, which was held in the city’s Cathedral Square, a block away. Police cleared the square shortly after 2 p.m. — about 20 minutes after the first shots were fired. Teachers were told there had been a firearms incident and that their schools were in lockdown. Lyall and her staff dispensed tea and WiFi passwords until the children were released.

“I’m used to this,” said Lyall, an American who has been here for three years. “I went into crisis management mode. The difference here is how New Zealand has reacted — calling it a terrorist attack immediately, and already they are talking in Parliament about the gun laws.”

No public vigil has yet been planned — the police have warned against large gatherings. The mayor, Lianne Dalziel — a former Labour member of Parliament whose tenure has been dominated by the politics of earthquake recovery — told people to do the things they already know are vital to community well-being. “Reach out to neighbors. Organize get-togethers and reflect on what has happened and how important neighborhoods are,” she said. “That’s what got us through the earthquakes, and that’s what will get us through this tragedy.”

To the extent that people were gathering Saturday, it was at Hagley Community College, a large, liberal, multicultural school next to Hagley Park. There, the Muslim community waited to find out who died and who survived and struggled with the monumental task of burying so many in a way that is consistent with their faith and allows the investigative process to take its course.

Shuja Rehman, a 32-year-old electrical engineer, came from Hagley College to the central police station to report his cousin, Syed Areeb Ahmed, as a missing person. Syed hasn’t been heard from since the assault began at the Deans Avenue mosque, where he had gone to pray. Shuja would have been there himself if he had not been delayed by a phone call. He heard the shots as he made his way along the street to the mosque. He has a friend who survived because he was covered by the bodies of others. He fears the worst for his cousin.

Shuja and Syed came to New Zealand from Pakistan as skilled migrants — Shuja has been here three years, Syed about 18 months.

New Zealand’s prime minister, Jacinda Ardern, says the slaughter carried out Friday “is not the New Zealand that this community knows,” referring to the Muslims. It is true that New Zealand has, until now, been largely free of terrorism and organized political hatred. Many here say they want to believe New Zealanders are collectively resilient to the kind of politics they observe, with abhorrence, in the United States.

The killer was Australian, many note, not someone born and bred here.

But Shuja suggested he has seen a less innocent side of New Zealand, describing casual racism and contempt directed his way at his workplace.

“Oh, you’re a Muslim, you must be a terrorist,” he said one colleague told him in his first week at work. He said he has been the butt of puerile generalizations about Islam and has had colleagues who openly mocked the rituals of Muslim prayer. He noted that as a nation, New Zealand has learned to celebrate Lunar New Year, Diwali and other ethnic festivals — but not Eid.

He chose New Zealand over Australia as a place to build a new life because this country seemed free of the racism he heard was prevalent across the Tasman Sea. Yet he has discovered, he said, that strangers here are willing to denigrate his faith and ridicule his community.

“We have not been speaking up,” he said as he waited to find out if his cousin was dead or alive, so that he could inform Syed’s desperate parents in Pakistan. “From now on, I will raise my voice.”