Updated

Police say they have a suspect in custody in the brutal murders of five people found dead in a San Francisco home Friday, KTVU reports.

35-year-old San Francisco resident Binh Thai Luc was arrested and charged with five counts of murder, Police Chief Greg Suhr announced in a press conference Sunday.

The five victims, who have not yet been identified by police, were found in various places in the home in what police described as a "very bloody" crime scene that was one of the worst they have ever seen.

Suhr said Luc has a criminal record and is believed to have known the victims, though he declined to reveal other details of Luc's arrest.

He said they are also looking into Luc's possible gang ties, but the murders are not believed to be gang related.

Police had previously stated the murders may have been money or gambling related, though they had first suspected murder-suicide.

A relative told KTVU a family of Chinese immigrants lived in the home: a couple in their 60s, their 32-year-old son and 37-year-old daughter and the son's girlfriend, also in her 30s.

Property records show the home is owned by 65-year-old Hua Shun Lei. Police say four of the five victims were related.

Mo Iranmenesh, who is the family's tenant at a neighboring property, identified the daughter who lived at the home as Jess, and said she was always friendly and 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."

One of the woman's coworkers also spoke highly of her to KTVU.

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

Police say the another daughter of the couple who owned the home found the victims.

Officials found paint and bleach all over the home, but no sign of forced entry. They said they believe the public is not in danger, as the murders did not to appear to be random.

Police spokeswoman Cmdr. Lyn Tomioka said during a press briefing Saturday afternoon the crime scene was so tangled it was hard to assess what exactly had happened.

"It could take days to process," Tomioka said. "We are working around the clock to determine what happened here."

Mayor Ed Lee called the incident a terrible tragedy.

"As the San Francisco Police Department thoroughly investigates this incident, I extend, on behalf of the city, our support and sympathy to all family members and friends of the victims involved in this crime," Lee said in a statement.

Police also arrested Luc's brother, 32-year old Brian Luc, on unrelated charges of drugs and ammunition possession and probation violation.

Suhr said the brothers lived together, but did not provide any other details on Brian's arrest.

Click here for more on this story from KTVU.com.

The Associated Press contributed to this report.