A Southeast Washington man who mistakenly thought a neighbor let a dog soil his lawn killed the man by stabbing him in the back, a detective said in court Thursday.

Ellsworth Colbert, 56, is charged with second-degree murder in the March 4 fatal stabbing of Robert Leroy Wright, 36. Wright was walking Macho, a friend’s pit bull, according to authorities, and as the dog neared Colbert’s yard, Colbert emerged from the house holding a knife and an aluminum walking stick.

Colbert accused the dog of fouling his yard, a D.C. homicide detective, Kenniss Weeks, told a D.C. Superior Court judge Thursday. But there was no evidence that the dog did more than walk on the grass, Weeks said.

Colbert and Wright argued, Weeks said, and after Wright turned his back on Colbert, Colbert began striking him on the head. Wright defended himself, reaching for a nearby shovel and striking Colbert with it, Weeks said.

Colbert was “the initial aggressor,” according to Weeks, who said his statements were based on interviews with two eyewitnesses. “He was yelling and he was angry.”

The confrontation began in front of Colbert’s home, in the 3500 block of Pope Street SE, Weeks said. Then the two men walked to the nearby 3600 block of Highwood Drive, where the dog’s owner lived and the fatal stabbing occurred, Weeks said.

A medical examiner’s report showed that Wright died of stab wounds to his neck, chest, abdomen and back.

Police later found four knives under a quilt on Colbert’s bed, Weeks said. Colbert also told police that Wright had attacked his son, according to Weeks, who said there was no evidence of such an attack.

During the hearing, Colbert’s attorney, James Beane, characterized Wright as a neighborhood “bully.” But Magistrate Judge Frederick Sullivan interrupted Beane, indicating that it would be too soon to argue self-defense because a determination on that issue would have to be made during a trial.

“The defendant was the aggressor, and self-defense isn’t going to be easy,” Sullivan said.

During the hearing, Colbert appeared to become incoherent, and Beane requested a short recess so Colbert could get a drink of water. Beane said his client was diabetic and had lung-related illnesses that made breathing difficult.

Assistant U.S. Attorney Robert Feitel called the attack “brutal” and an example of Colbert’s “explosive rage.” He cited several previous assault charges against Colbert in the District and Prince George’s County from 2005 to 2010.

“We believe this man is very dangerous and has demonstrated that multiple times,” Feitel said.

Sullivan ordered Colbert held in jail ahead of a hearing scheduled for July 12.