A man armed with an assault weapon ambushed and killed two Louisiana deputies who were investigating an earlier unprovoked attack in which another deputy was shot and injured, the local sheriff said Thursday.

St. John the Baptist Parish Sheriff Mike Tregre described the chaotic, violent scene while choking back tears. In all, two deputies were shot and killed and two were shot and injured.

The motive is unclear, Tregre said. Also unknown is whether the gunman in the first shooting is the same as in the second. Both incidents took place early Thursday morning in a small community about 25 miles west of New Orleans.

Five people are in custody, but have not yet been identified, the Associated Press reported.


Tregre struggled at times to maintain his composure during a televised press briefing Thursday morning.

“I lost two good officers today,” he said, and he asked for the public’s support in a video posted online at local TV station website WWLTV.com: “Please pray for the two officers that were ambushed earlier this morning.”

The slain sheriff’s deputies were identified as Brandon Nielsen, 34, of Destrehan, La., described as a husband and father of five children, and Jeremy Triche, 27, of LaPlace, La., who is survived by his wife and 2-year-old son.

Details are still unfolding in the case, but here’s what Tregre said happened:


The incident took place in the early morning as one of the department’s deputies worked a traffic assignment in a LaPlace parking lot serving the nearby Valero Energy plant.

“For some unknown reason at this time, a gunman opened fire on him multiple times,” Tregre said. That officer, Michael Scott Boyington, 33, of Kenner, La., was taken to a local hospital and is expected to survive.

The deputy’s colleagues launched into action at the news of the attack, and followed up on a citizen’s tip about a car seen speeding from the scene of the shooting.

Deputies traced that car to a nearby trailer park at about 5 a.m. While interviewing two of the men inside the trailer, deputies saw a third man who appeared to be fully clothed, but lying beneath a blanket, Tregre said. Deputies asked the man to come outside.


“Another person exited that trailer with an assault weapon and ambushed ... excuse me ... ambushed our two officers,” Tregre said, choking back emotion.

A fourth officer, Deputy Jason Triche, 30, of Montz, La., was also shot and injured during this incident. Deputies at the department were focusing on the investigation, and no one was immediately available to say whether Triche is related to the slain officer.

Tregre said Louisiana state police were taking over the investigation.

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