Michael K. Perry, 56, is being held in lieu of $20,000. He is also being held on two misdemeanor contempt warrants totalling $300.

The attempted-extortion charge stems from Perry allegedly threatening a man, 49, who is his roommate, with a knife yesterday at 2:55 p.m. on the 1900 block of Colburn Street to recover $200 he claims the complainant stole from him.

Perry allegedly held the pocketknife to the complainant's throat.