MIAMI -

A public memorial service has been planned for Monday to honor two Miami-Dade police officers killed in action.

Officers Roger Castillo and Amanda Haworth died Thursday when they were shot while trying to serve an arrest warrant on a murder charge.

Facebook Page: In Memory Of Officers

Police said the two officers, along with two others, went to a home in Liberty City to serve 23-year-old Johnny Simms with a murder warrant and he began shooting. According to police, after Simms shot the two officers, one of the surviving officers fatally shot him.

A memorial service for Castillo and Haworth has been scheduled for 11 a.m. Monday at the American Airlines Arena.

Meanwhile, detectives are spending hours on tracing the events that led up to the shootout. Emotions were raw at the Miami-Dade Police Department as a focused investigation began into the procedure, timeline and actions that led to the ambush and killings of Castillo and Haworth.

"It's more than just heartbreaking," said Miami-Dade Police Director James Loftus.

Investigators said the slain officers were well trained, experienced and well armed.

"If someone has the element of surprise, if someone bursts out of the bedroom and they're firing at you as they come out of the bedroom, you're at God's mercy," Loftus said.

Police said there is no dispute that Simms came out of a back room firing a semiautomatic handgun as three out of the four officers entered the house to serve the arrest warrant.

"They're going to tell their story, and I'm going to tell my story," said Simms' mother, Lorraine Simms.

Lorraine Simms said her son told her to open the front door and let the officers inside while he waited in the hallway. She said she did not know he had a gun.

Statements from Simms' family indicated they knew officers were looking for him, according to police. Family members insisted they did not know Johnny Simms would come out of the back of the house firing a gun.

"I don't know any of these answers to questions that you're asking me about, and right now, I really don't care," said Lorraine Simms.

"They do this every day, and you don't hear about it because it's done safely," Loftus said. "A motivated, evil person who is armed and intent upon doing damage to you has the upper hand, always."

A fund has been set up to help the families of the fallen officers. All of the money donated will go to the families.

The Love Fund c/o Dade County Police Benevolent Association, 10680 PBA Memorial Blvd., Doral, FL 33172