Two local men were indicted Tuesday for allegedly operating a drug ring out of Harvard Square, according to the Middlesex County District Attorney's office.

Steven M. Potter, 19, of Dorchester, and Arthur Kraus, 21, of Winchester, are charged with possession of LSD with intent to distribute. They face additional charges under a new state law imposing extra penalties on those who sell drugs within 1000 feet of a public or private school.

They are scheduled to be arraigned in Middlesex Superior Court on May 30, said Marsha Cohen, a spokesperson for District Attorney L. Scott Harshbarger '64.

Cambridge police arrested the men on January 5, after executing a search warrant at a Somerville home, court documents said.

In the apartment, police found precision scales, syringes, vials, $1500 in cash and what appeared to be LSD and marijuana, according to an affidavit filed by the officers.

The bust capped off a five-month undercover investigation by Cambridge and MBTA police into sales of LSD in Harvard Square. Police said they purchased hundreds of "hit" of acid from Potter over a three-month period.

One of the alleged buys was made in the Au Bon Pain cafe in the Harvard-owned Holyoke Center. Harvard police said they were aware of the investigation but had no role in it.

Harvard Square has long been known as one of the most popular places in New England to purchase LSD and other hallucinogens. At the time of the arrests, police said they expected the bust to have a "substantial impact" on drug sales in the Square.