Four law enforcement officers were shot dead and four wounded Monday afternoon in Charlotte, North Carolina, as they were serving warrants to a felon illegally possessing firearms.

The shooter was also shot dead during the confrontation, police said, on the deadliest day for US law enforcement in recent history.

Around 1:30 pm Monday, a group of officers from the Charlotte-Mecklenburg Police Department (CMPD) and the US Marshals Fugitive Task Force went to serve warrants to Terry Clark Hughes Jr, 39. He was wanted for being a felon possessing a firearm and for eluding arrest.

Police said in a statement that when the officers approached the house where Hughes was, he opened fire with a "high-powered rifle". The gunfire struck several officers. Immediate response was requested and the gunfire continued, hitting more officers.

The standoff lasted three hours, according to The Associated Press.

"There's indication that the suspect saw them coming to the house prior to them getting to the front door," Johnny Jennings, the chief of the CMPD, said during a news conference Tuesday.

Jennings said the suspect used an AR-15-style rifle and a 0.40-caliber handgun, and he had additional ammunition for both weapons. Police were investigating how he acquired them.

Hughes was initially shooting from the upstairs of the house, police said. "Even though our officers were trying to take cover, they were at a disadvantage because the suspect was up at a higher level, and they were trying to return fire from a lower position to an elevated position," Jennings said.

Police initially believed there were two shooters. On Tuesday, Jennings said it was likely Hughes was moving through different parts of the house firing.

Hughes then left the house while armed; officers opened fire and shot him in the front yard, where he was found dead, police said.

After a long standoff and negotiation, two women — one 17 — came out of the house and were taken by police for questioning. Police said that they are cooperating with the investigation.

In total, eight officers were hit, and four of them died. The deceased included Sam Poloche and Alden Elliot, both 14-year veterans of the North Carolina Department of Adult Correction and assigned to the US Marshals Carolinas Regional Fugitive Task Force; Deputy US Marshal Thomas Weeks Jr and CMPD Officer Joshua Eyer.

The three US marshal's officers died on the scene, and Eyer died with his wife and family by his side after fighting for several hours, police said.

The four wounded — three CMPD officers and one US marshal — are in stable condition, police said.

"Today is an absolute tragic day for the city of Charlotte and for the profession of law enforcement," Jennings said in a post on social media on Monday. "Today, we lost some heroes that are out simply trying to keep our community safe."

President Joe Biden said in a statement late Monday: "They are heroes who made the ultimate sacrifice, rushing into harm's way to protect us. We mourn for them and their loved ones. And we pray for the recoveries of the courageous officers who were wounded."

Eventually, armored vehicles smashed into the house, ripping off windows and entire doorways.

Local station WSOC-TV said its helicopter captured an armored vehicle driving through yards and knocking over recycling bins before officers removed a person with a bloodstained shirt. The helicopter pilot said he couldn't show the front lawn of the home because the scene was graphic and disturbing.

According to the Fraternal Order of Police, 2023 had the highest number of police officers shot since the organization started to collect such data — 378 — with 46 killed.