Matthew Gerald's bravery and enthusiasm for his new job -- Baton Rouge police officer -- was no surprise to Ryan Cabral, who served with Gerald on a helicopter crew in Iraq.

"Like most other police officers, they go where they're needed," Cabral, an Army veteran and police officer in Temple, Texas, said in a telephone interview Monday night. "They know what the dangers are, but that's how they're made. They're made to serve."

The 41-year-old Gerald was one of three officers killed Sunday in what police called an ambush by a lone gunman, who also died. The shooting traumatized a nation already on edge.

Cabral remembers Gerald as a man of infectious enthusiasm for anything he took on.

So does Gerald's neighbor, Ashley Poe. She recalls a few months ago when Gerald was fresh out of the police academy, proudly washing his new police cruiser in the driveway of his home under a blazing Louisiana sun. She watched as he flicked the blue lights on and off, on and off.

Poe and her husband shared a laugh. The former soldier and Marine looked like an excited kid.

"It's like living out the dream," she said.

That dream ended Sunday.

Others killed were 45-year-old Brad Garafola, an East Baton Rouge Parish sheriff's deputy and a father of four; and 32-year-old Montrell Jackson, a 10-year veteran of the Baton Rouge Police Department with a newborn baby at home.

The three are among 10 law enforcement officers killed over a span of 10 turbulent days around the country by attackers - at a protest march in Dallas, a courthouse in Michigan and now a convenience store in Baton Rouge.

The officers who died Sunday all lived in the area of Denham Springs, a quiet bedroom community across the Amite River from Baton Rouge, which has been in turmoil for two weeks. Tensions rose sharply after the death of Alton Sterling, 37, a black man killed by white Baton Rouge officers after a scuffle at a convenience store. The killing was captured on cellphone video.

As the nation debates race and policing, this community is mourning three of its sons -- all husbands and fathers described by friends as being committed to protecting and serving the public.

"You hear about these things happening across the country to officers just trying to defend us, but this brings it right here, to our home," Livingston Parish President Layton Ricks said. "These are our families. These are good men. They're the only line of defense between good and evil. We say we don't want to let this evil affect how we live our daily lives. But it does."

Gavin Long, a former Marine from Missouri dressed in black and carrying extra ammunition, opened fire on officers about 8:45 a.m. Sunday, police said.

Garafola and Gerald were white. Jackson was black, as was the gunman.

"The world is crazy right now. It is complete chaos," Jackson's sister-in-law Lauren Rose said. "And it all needs to stop, everything.  We all need peace."

Three other officers were wounded. One of them, Deputy Nicholas Tullier, remained in critical condition Monday. The gunman was killed at the scene.

Poe watched from the window Sunday morning as a line of police cars pulled up in front of Gerald's house. She woke up her husband, a former city police officer.

"He said, 'What's wrong?' and I said, 'There's units everywhere, and you've told me that's never a good sign,"' she said. They turned on the news.

The gunman shot Gerald and Jackson first.

Gerald was a Marine from 1994 to 1998. He later joined the Army and served as a decorated soldier from 2002 to 2009, including three tours in Iraq. Less than a year ago, he joined the Baton Rouge Police Department.

He had a wife and two daughters, Poe said, and was devoted to them.

Poe said her 14-year-old son was interested in the military, and Gerald was always ready to answer his questions.

Denham Springs, population 10,000, is the sort of town where everyone is connected, said Mayor Gerard Landry. There's a palpable sense of anger and despair.

"There's no way to describe what it does to a small city like this," Marilyn Wallace said Monday, standing behind the counter of the store she and her husband, Randy, own on a two-block long stretch of antique shops in the historic district of Denham Springs.

The city is in Livingston Parish, about 13 miles from Baton Rouge, with a history of racial tension. But that history -- and the racial divide in nearby Baton Rouge -- seem remote here.

Jackson's father-in-law, Lonnie Jordan, called him a "gentle giant" -- tall and stout and formidable looking, but with a peaceful disposition.

Jordan said his son-in-law had been working long hours since Sterling was killed.

Jackson posted on Facebook that he was physically and emotionally tired. He wrote that while in uniform he gets nasty looks and out of uniform some consider him a threat.

"I swear to God I love this city," he wrote, "but I wonder if this city loves me."

The police chief described at a news conference how he had gone to the district where Jackson worked just days earlier in an attempt to boost the spirits of the officers. Instead Jackson ended up giving him the pep talk.

He had been on the force 10 years and risen to the rank of corporal, said Kedrick Pitts, his half brother. He worked hard, sometimes seven days a week.

He was funny and good natured, Pitts said. He collected shoes, 500 pairs, including special Kobe Bryant and Michael Jordan lines.

But what he loved most was his wife and 4-month-old son.

"He's going to grow up without a father," sister-in-law Rose said. "But we'll be there to give him memories and let him know how his dad was a great man, and how he died with honor ... Hopefully one day, he'll be like his dad."

At the convenience store Sunday, Garafola tried to intervene and help the fallen officers.

Surveillance video showed Garafola firing at the gunman from behind a dumpster as bullets hit the concrete around him, East Baton Rouge Parish Sheriff Sid Gautreaux said.

"My deputy went down fighting. He returned fire to the very end," the sheriff said.

Garafola's friends described him as a man committed to public service and devoted to his family.

He had a wife and four children: a 21-year-old son, a 15-year-old daughter, a 12-year-old son and a 7-year-old daughter.

Sgt. Gerald Parker, a close friend, described him as a "jack of all trades" who enjoyed helping people in his neighborhood, like mending their fences or mowing their lawns. He worked hard, often picking up extra hours.

"He was a man of strong character," Parker said. "All these officers are heroes. Some people would run. But these gentlemen leave their families knowing something can happen."