SAN FRANCISCO (CBS SF) – The San Francisco plumber accused of the gruesome slayings of five people inside a home near City College of San Francisco has pleaded not guilty to murder charges.

Binh Thai Luc entered his plea Thursday to five counts of murder, plus special circumstances of committing multiple murders, robbery, burglary and lying in wait.

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The 35-year-old appeared nervous and shook his head several times during the 20-minute hearing in San Francisco Superior Court. A judge set his bail at $25 million.

KCBS’ Bob Melrose Reports:

Mark Goldrosen, the private attorney appointed to represent Luc, did not oppose the amount. Luc was previously being held without bail because of a federal immigration hold against him.

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Prosecutors have said Luc used a blunt instrument to kill 32-year-old Yuan Ji “Vincent” Lei, Lei’s parents and Lei’s girlfriend on March 23. The bodies were found by a relative at the family’s home in the city’s Ingleside District.

The medical examiner’s office has identified the other man killed as 65-year-old Hua Shun Lei and the women as Wan Yi Xu, 62, Chia Huei Chu, 30, and Ying Xue Lei, 37.

Authorities have not discussed a possible motive, but say they believe the victims were targeted.

Luc will return to court on May 3 for a status conference and to set a preliminary hearing date.

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