Police in Baton Rouge, La., revealed grisly details Monday of a shooting standoff in which the suspected gunman ambushed two officers sent to interview him about a killing hours earlier, then allegedly stood over a dead officer’s body while continuing to shoot him at point-blank range.

Ronnie DeWayne Kato Jr., 36, engaged in a four-hour standoff with officers and SWAT team members on Sunday while he was barricaded in a house, investigators. One officer was killed while another remained in critical condition but was "doing a lot better," Sgt. L'Jean McKneely Jr., a spokesman for the Baton Rouge Police Department, told reporters Monday.

Earlier in the day, Kato allegedly ambushed his girlfriend of 18 years at her mother's house, kicked down the door and pistol-whipped her, according to an affidavit supporting the first warrant for Kato's arrest.

BATON ROUGE OFFICER SHOT DEAD, ANOTHER WOUNDED, POLICE SAY; SUSPECT IN CUSTODY AFTER STANDOFF

The girlfriend's mother stopped him before he entered the house, but he went back outside, retrieved a rifle and shot and killed a man at the house, who was one of five adults living there, detectives said. Police identified the man as Curtis Richardson, 58, news outlets reported.

Officers then went to the house for a "knock and talk" with Kato and tried to secure the backyard to prevent him from escaping, the second affidavit read.

Police did not immediately identify the two officers involved in the shooting but said the officer who died was a 21-year veteran of the police force.

Evidence, including what appeared to be close-contact wounds, indicated that Kato had stood over the dead officer's body and kept shooting him, the statement read.

Kato was arrested on two counts of murder, six counts of attempted murder, five counts of home invasion and one of aggravated battery.

His girlfriend said Kato had threatened to kill police several years ago, threatening to "Gavin Long" officers, according to a complaint the girlfriend filed against him in 2017. That was a reference to Gavin Eugene Long, whose case from four years ago in Baton Rouge bore familiarities to Sunday's shooting incident with Kato.

Long was a member of a black anti-government movement who shot six police officers in 2016, killing three and wounding three others. He was arrested after an hourslong standoff in which shots were exchanged with a SWAT team. That ambush unfolded two days after a white officer shot and killed a black man in Louisiana's capital.

Kato did not have any known links to such groups, McKneely said.

Despite the complaint by Kato's girlfriend, no charges were filed against him, according to reports by The Advocate.

Prior to that, Kato had two drug possession cases against him, in 2001 and 2010, but charges against him were dropped in the second case.

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Civil court records also showed no signs that Kato's girlfriend or anyone else had requested temporary protection from abuse, the newspaper reported.

The Associated Press contributed to this report.