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There is no official set of criteria or definition for a mass shooting, but the F.B.I. considers mass murder to be a spasm of violence perpetrated by one person that takes at least four lives in the same location. By that metric, we’ve already had several just this month. And if the wounded are counted, the tally grows even higher.

* On Nov. 1, four people were shot, two of them fatally, outside a nightclub in Fayetteville, N.C. Cornelius Tobias Jackson, 26, and Melissa Yamile Neal, 24, were killed, and Latoyia Whitted, 20, and John Mills, 40, were wounded. Several people have been questioned but no arrests have been made.

* On Nov. 3, four people were shot and wounded outside a restaurant and nightclub in Perris, Calif. Jose Luis Avalos, 36, was arrested at a hospital, where he was being treated for a gunshot wound sustained when a security guard returned fire. There had been fighting among the club’s patrons that night, but police said the victims had not been involved.

* On Nov. 6, 10 people were shot, three of them fatally, at a barber shop in Detroit, Mich. The shooter fired a few shots into Al’s Barber Shop, where a gambling session was under way, waited for people to come out and then opened fire on the crowd. Larry Walker II, who has been named as a person of interest, was wearing body armor when he was detained by the F.B.I. the next day. Detroit Police Chief James Craig called the violence “urban terrorism.”

* On Nov. 7, four people were shot and wounded when someone opened fire near a bus stop in Northeast Washington, D.C. The suspect, 51-year-old Victor Leon Coley, had been seen arguing with two of his victims before the shooting. The other two victims were bystanders. Coley was arrested and charged with four counts of assault with intent to kill.

* On Nov. 10, two teenagers were killed and 19 others were injured in a shooting at a house party in Cypress, Tex. Willie Young, 21, and Randy Stewart, 18, were taken into custody the next day; Young has since been released.

* On Tuesday, a man shot and killed his wife, 14-year-old daughter and brother-in-law before taking his own life in Phoenix, Ariz. Michael Sanders, 53, had reportedly terrorized his wife, 51-year-old Carol Sanders, who had filed a restraining order against him and was in the process of moving out when she was killed. The order of protection extended to their daughter’s school and wife’s place of work.

Here is today’s report.

—Jennifer Mascia

A 25-year-old man and his 7-month-old son were shot to death in an apparent ambush while driving towards the Crescent City Connection in New Orleans, La., Wednesday night. The victims were riding in the back of a black Honda sedan when someone in a dark-colored vehicle opened fire on the car. The man was shot multiple times and his son, who was fastened in a car seat, was shot in the head. The infant is the youngest murder victim in New Orleans this year. Detectives do not believe the shooting was random. No suspects have been named.

—NOLA.com

Three teenagers were wounded in a shooting near Brashear High School in Pittsburgh, Pa., Wednesday afternoon. One victim was grazed in the head, another was grazed in the neck and shoulder and the third student was shot in the foot and arm. The teen who was shot in the head staggered back to campus, where administrators pulled him inside. Police and a SWAT team surrounded the school and searched the nearby woods before converging on two houses, taking five young men and a young woman into custody. The victims are not cooperating.

—The New York Times

Two men were shot to death and three others were wounded across Chicago, Ill., Tuesday night. Uriel Quinones, 20, was killed when a van pulled up alongside him and someone opened fire in the Heart of Chicago neighborhood; 53-year-old Michael Sullivan was shot to death in the East Garfield Park neighborhood; an 18-year-old sustained a graze wound to the head; a 20-year-old man in a wheelchair was being pushed by a friend when someone he knew walked up and shot him in the knee; and a 32-year-old man was shot in both arms and one of his legs. On Wednesday afternoon, a man was killed and another man was wounded in a shooting at a gas station in the Englewood neighborhood.

—Chicago Tribune

Charles Timothy Nichols, 58, and his son Charles Timothy Nichols, Jr., 29, were shot and killed at Salem Lake in Winston-Salem, N.C., Wednesday morning. Police are not searching for any suspects. Several weapons were found at the scene.

—My Fox 8

Robert Land, 63, was killed and his wife, Sue Land, 60, was critically injured in a shooting in a home in Spring Hill, Tenn., early Wednesday. Police said there were no signs of forced entry but they were not ready to declare it a domestic shooting.

—The Tennessean

Malik Schexnayder, 17, was found shot to death on the front lawn of a home in Avondale, La., Wednesday afternoon. Witnesses said they heard several shots fired and saw a group of men run from the scene. Police are soliciting tips.

—NOLA.com

27-year-old Paul Danny Khmabounheuang was shot and killed and two others were wounded in a gang-related robbery attempt in Wichita, Kan., Wednesday afternoon. One of the victims was found in the street, and police followed a blood trail to the deceased man. The third victim was found outside a nearby apartment complex. Two suspects are in custody.

—KAKE.com

54-year-old Stephen J. Dollarhide was found shot to death in a home in Midwest City, Okla., Wednesday morning. Dianna Elaine Sanders, 49, who lived with the victim, called police from a pay phone two blocks away and asked a dispatcher to send an ambulance to the home because she had just shot a man. She was arrested.

—News9.com

Jesus Escobedo, 38, was shot and killed during a home invasion in west Harris County, Tex., early Wednesday. The victim’s wife told investigators she and her husband were sleeping when they heard a loud crash at the front door. Three men who had their faces covered then rushed into the bedroom and made demands, though the victim’s wife could not say what they were. So far, investigators have no motive.

—Chron

William Riddick, 24, was shot and wounded near Mont Pleasant Middle School in Schenectady, N.Y., late Tuesday. He died the next day. Police are investigating.

—CBS 6 Albany

25-year-old Ricardo Silva was shot and killed in Oxnard, Calif., Wednesday evening. The victim’s girlfriend, who is expecting their first child, said two men approached them as they walked down the street. An argument ensued, followed by gunshots. Police are hoping witnesses come forward.

—KABC-TV

A man was shot and killed in downtown Grand Island, Neb., Wednesday evening. Police released few other details.

—KHASTV.com

A woman was shot in the head and critically injured outside a home on the west side of Detroit, Mich., Wednesday night. The shooting was preceded by pounding on the front door. Police are looking for the shooter.

—MyFoxDetroit.com

A mother of three shot and killed herself at her home in Bradenton, Fla., Wednesday afternoon.

—Bradenton Herald

David Michael Canter, 26, was shot and wounded in a home in Rio Grande, Ohio, Wednesday evening. A suspect is in custody.

—WSAZ 3

A 43-year-old man was shot and wounded during an argument inside a Benihana restaurant in Dearborn, Mich., Tuesday night. Police are following up on leads, and said the shooting was not random.

—CBS Detroit

A man was shot and wounded at a car wash in Lakewood, Colo., Wednesday afternoon. The gunman was in his car when he fired. Anyone with information is asked to call police.

—The Denver Post

A man was shot in the back and critically wounded at a Baton Rouge, La., intersection Wednesday night. No other details have been released about the shooting, which remains under investigation.

—The Advocate

A man was wounded in a possibly gang-related shooting at a gas station in San Pedro, Calif., Wednesday afternoon. Police said the gunman was a passenger in a parked car who got into a dispute with a man getting gas. The gunman fired several shots and wounded the man, then fled.

—Daily Breeze

An 18-year-old woman was shot and wounded in Milwaukee, Wis., Tuesday night. Police are investigating.

—Fox6Now.com

According to Slate’s gun-death tracker, an estimated 10,491 people have died as a result of gun violence in America since the Newtown massacre on December 14, 2012.