There wasn’t anything particularly ominous about a video posted on Cedric Ford’s Facebook page earlier this week. Ford, heavily tattooed and seen with a scrappy beard and a shaved head, danced around in an undershirt as Drake’s “Summer Sixteen” played in the background and a woman looked on. Thirty seconds of jumbled images — that was it.

The Kansas man, who authorities have identified as 38-year-old Cedric Larry Ford from Newton, is said to have killed three people at the lawn mower factory where he worked, however. Following the Thursday-night shooing rampage, “Summer Sixteen’s” hook — “Looking for revenge” — sounds a lot different.

Authorities say Ford was the gunman who opened fire at multiple locations in Harvey County, Kan., killing three people and injuring 14 others before he was shot and killed by police.

Police said Friday that the bloodshed began not long after Ford was served with a restraining order barring him from contact with someone he had abused.

Harvey County Sheriff T. Walton told reporters that Ford was served with a “protection from abuse” order while he was working at Excel Industries, a manufacturing plant in Hesston where he worked as a painter.

Sheriff’s deputies who gave him the order said Ford seemed “upset, but nothing greater than anybody else who gets served” with an order, Walton said. Walton said he could not go into further detail about the order.

About 90 minutes after Ford was served with the restraining order, Walton said, the first shots were fired.

The gunman shot two people and stole a car at 12th and Meridian in Newton before heading for at Excel Industries, authorities said.

Armed with a pistol and a long gun, they said, the shooter killed three inside the factory before he was fatally shot by a police officer.

“I’ve never seen anything like this,” the sheriff said Friday. “He was randomly shooting people.”

Michael Dellinger, an employee at Excel, told The Post in a phone interview that he felt there was something “real off” about Ford from the start, even though he was always “smiling and laughing” and “didn’t seem like an angry person.”

Another Excel worker, Matt Jarrell, told CNN that Ford was “a mellow guy” to whom he could talk about anything.

Yet, Dellinger said Ford gave him a “bad gut feeling.” They used to take smoke breaks together, he said, and Ford recently told co-workers that he had just purchased a new truck as well as a new stereo system for his car.

“A lot of people said he had gotten fired, or that he was worried about getting fired,” Dellinger said.

Adam Mullet, a vice president at Excel, said he was not sure what could have motivated the attack.

“I have no names of victims or why” the shooter “did what he did,” Mullet wrote in an email to The Post. “I have only the sorrow for our family. Our Excel family.”

Brian Johnson, an Excel employee who worked in the paint and powder department with Ford, said he believes he was one of the shooter’s targets. Johnson escaped the attack without any injuries, but he was at Via Christi Hospital St. Francis in Wichita on Thursday night visiting a co-worker in critical condition.

According to Johnson, Ford had worked at Excel for five years. The two men argued over the phone Wednesday night, Johnson told The Post, and Ford “thought everybody was out to get him.”

Johnson wouldn’t explain the nature of the disagreement. He said he hoped to settle the dispute at work; but when he arrived, Ford was on break.

“Went to go pick up his guns, I guess,” Johnson said.

Walton, the Harvey County sheriff, said Friday morning that investigators did not yet know how Ford — who had a criminal record in Kansas as well as Florida — had obtained the guns he had during the shooting.

“He’s been in my jail a couple of times before,” Walton said.

According to public records, Ford has an extensive criminal history, including charges for burglary, fleeing police officers, grand theft and an unspecified felony. Most of the incidents occurred in Broward County, Fla., and date back to 1996.

A 1997 Miami Herald story said Ford was arrested that year after he was seen breaking into a car with two accomplices. In 2008, he was convicted in a misdemeanor brawling case in Kansas, the Wichita Eagle reported. Earlier this month, he was accused of assault by a live-in girlfriend.

“He placed me in a chokehold from behind,” she wrote in a request for a protective order filed Feb. 5, according to the Eagle. “I couldn’t breathe.”

She added, in all capital letters: “He is an alcoholic, violent, depressed. It’s my belief he is in desperate need of medical & psychological help!”

Most recently, Ford lived alone in a mobile home in Newton, about eight miles from Excel.

Ernie Carson, the property manager at his home, said when Ford filled out a rental application, he was asked about his criminal history and “admitted that he had done wrong, but that was all back in Florida and he came up here to turn his life around.”

“Everybody makes mistakes,” Carson said, “but you can’t expect something like this.”

Carson said that not long before the shooting, a neighbor of Ford’s called him to complain that he was playing his music too loudly. When Carson went to the neighbor’s unit before heading to Ford’s, he saw Ford walk out of his front door with two guns — the long gun and pistol authorities would later say he had with him during the shooting.

“She said it was the biggest gun she’d ever seen,” Carson said. “I told her to call the police, but I don’t know if she did.”

Ford’s Facebook page showed his interest in hip-hop, restaurants and cars — and, in recent months, guns. A photo from January shows him sitting in the front seat of a car with a handgun on his lap and what looks like a bottle of vodka between his legs. In a video posted last September, he is seen shooting a semiautomatic rifle into an empty field.

Among the pages he “liked” were “Love My Glock,” “AK-47” and “Magpacker,” a gun shop in Texas.

Posted by Cedric Ford on Sunday, September 20, 2015

Before the gun images appeared, Ford’s Facebook page largely featured a young boy and girl, with whom he played mini-golf and visited the zoo.

Sarah Kaplan, Jacob Bogage and Christopher Haxel contributed reporting. This post has been updated.