The San Francisco Police announced Sunday evening that a suspect had been arrested that morning in connection to the brutal murders of five local residents, who were found dead days before in a scene described as among the worst officers had ever seen.

In a 5 p.m. press conference, Police Chief Greg Suhr announced that 35-year-old San Francisco resident Binh Thai Luc had been arrested that morning and booked on five counts of murder.

The announcement came just two days after the victims were found dead by a close relative inside their home at 16 Howth St., near the City College of San Francisco at 7:47 a.m. Friday morning.

Police described the murder scene as "very bloody" and among the worst they've seen. Suhr noted that a man was found in the threshold of the home, while a man and woman were found in the garage, another woman was found upstairs and a third woman was found downstairs.

There was bleach and paint all over the home, as if someone was trying to disturb the scene, police had said earlier.

"This was a complex crime scene. We had five deceased persons apparently from blunt force trauma. We didn't know what we had," Suhr said.

Evidence gathered during an intense investigation over the next two days resulted in SWAT teams executing search warrants Sunday in San Francisco and San Mateo counties, and finding the suspect Luc.  

Suhr declined to release details of the arrest or what led investigators to Luc, but he was described as knowing all five of the victims and as having a criminal record.

According to Suhr, the murder investigation was still ongoing Sunday, and that San Francisco medical examiner was still trying to confirm the cause of death for the five victims, though it was evident that they had experienced blunt force trauma and that an "edged weapon" was used in their slayings.

Two police sources told KTVU Friday night that the murders appeared to have been a targeted attack, possibly over money, and not a murder-suicide, as previously thought.

Suhr said that investigators were looking into Luc's possible gang ties, though it was believed that these murders were not gang-related.

Also arrested was Luc's 32-year-old brother, Brian Luc, on unrelated charges of drugs and ammunition possession and violation probation.  Suhr did not provide details of the younger brother's arrest, saying only that the two lived together.

Suhr also made it clear during the press conference Sunday that killings were an isolated case.

"I want to continue to reassure the public that this incident was specific to 16 Howth St.," said Suhr.

A relative of the victims said the family who lived in the home were immigrants from China: a couple in their 60s, the couple's 32-year-old son and 37-year-old daughter, along with a woman in her 30s who was in a relationship with the son.

Property records indicated that the homeowner was 65-year-old father Hua Shun Lei.

Another daughter in her 40s, who did not live at the residence, was described as the woman who discovered the bodies and called 911.

Miriam Mendoza-Moody, a neighbor, said she heard yelling from inside the home.

"I did hear around midnight some very loud male-voice person arguing or yelling," she said. "It was discomforting, and my dog became agitated."

Mo Iranmenesh rents the home next door to the victims' and said the family owns the home he lives in. He said the 37-year-old daughter named Jess was always helpful.

"She's friendly," he said. "Every time I need help, she's there. Every time I lock myself out, she'd let me in."

Iranmenesh said he heard the other daughter screaming after she found the bodies Friday morning.

"It was a woman shouting, 'Can someone help me?'" said Iranmenesh.

According to officials, the family moved into the home less than a year ago, and the father and son were in the construction business.

Howth Street between Ocean and Geneva avenues had been closed for much of Friday while police continued their investigation. Saturday, the house where the crime took place and two adjacent houses remained cordoned off by police tape.

Several bouquets of flowers laid on the sidewalk near the house since the shooting, one with a note reading, "R.I.P. Seff, you'll be missed."

Todd Sidebottom worked with Jess Lei, one of the family members who lived at the house and was presumed dead.

“I worked with Jess. She was an engineer at our company,” Sidebottom said. “(She’s a) real sweet person. One of the nicest people you'd ever want to meet.”

Mayor Ed Lee released a statement about the deaths Friday afternoon, calling them "a terrible tragedy."

"I extend, on behalf of the city, our support and sympathy to all family members and friends of the victims involved in this crime," he said.