NORTHAMPTON — A Sunderland man held on charges that he participated in a sex trafficking operation pleaded not guilty to five charges Friday in Hampshire County Superior Court, and had his bail reduced.

Jian Song, 48, was arraigned on charges of trafficking of persons for sexual servitude, keeping a house of prostitution, deriving support from prostitution, money laundering and conspiracy. His bail was also reduced from $100,000 to $75,000, $50,000 of which Song has already posted.

Song, his wife Feng Ling Liu, 50, her daughter, 26-year-old Ting Ting Yin, and 52-year-old Shuzi Li, were arrested in December as part of a probe — lead by the Northampton Police Department and the state’s attorney general’s office — into two separate sex trafficking rings that allegedly brought women from New York to local massage parlors.

Song faces similar charges in Hampden County, but the two cases have now been consolidated into the one case before the Hampshire Superior Court. Song, Liu and Yin are also expected to be arraigned in Middlesex County, though that case is also likely to be heard in Northampton.

Assistant Massachusetts Attorney General Elizabeth Vasiliades argued Friday that Song’s bail should remain at $100,000 because, she alleged, he was a flight risk facing a long stint in jail if convicted.

But Song’s attorney, Colin Keefe, argued that the $50,000 his client had already posted was more than sufficient. He said there was no evidence to suggest that Song knew what was going on in the massage parlors, and that he suffered a heart condition and worries about dying in jail.

“I’m going to split this baby,” Judge John Ferrara said before setting the bail at $75,000, meaning Song would have to post another $25,000 to make bail.

“We’re certainly relieved that Judge Ferrara saw that there was merit to the argument that the bail was too high,” Keefe said after the arraignment, though he was unsure whether his client would be able to post the remaining bail.

As part of the conditions set for bail, Song, who is in the United States on a green card, would be monitored via GPS and can not leave Massachusetts. He has already surrendered his passport to authorities.

Dusty Christensen can be reached at dchristensen@gazettenet.com.