Manoj P. Unni, 30, of the 9300 block of Cross Timbers Court, is facing one count each of possession of marijuana, possession with intent to distribute, possession of equipment to produce marijuana, and drug manufacturing, according to police department spokeswoman Sherry Llewellyn.
Detectives were led to Unni's home by an anonymous tip, Llewellyn said, which was followed by an undercover operation, including surveillance, that gave them probable cause for a search warrant.
Police arrived at Unni's home late Wednesday morning with a search and seizure warrant, and subsequently found what Llewellyn termed "a substantial marijuana grow operation in the basement, including sophisticated growing equipment."
They found 341 plants, which at full maturity yield about 170 pounds of marijuana worth $510,000, Llewellyn said. The plants were kept in two areas of his basement.
Police also found high-intensity lights, a dehumidifier, air filters, water pumping systems, lighting timers, a carbon dioxide system and a ventilation system, all of which can be used in growing the plants.
"Our investigation doesn't end here. It really begins here," Llewellyn said. "We don't anticipate any other arrests for this particular growing operation, but our investigation will continue for what was happening with those drugs after they left his residence.
"At this point there's no indication that this is connected to anything of a larger scale."
Baltimore Police confirmed that Unni worked for the agency as a crime lab technician from 2003 until January 2006. Anthony Guglielmi, the department's chief spokesman, said he could not comment on why Unni separated from the agency.
The marijuana and books on growing it are being kept in a room at the Howard County Police Department. The marijuana will be destroyed, Llewellyn said.
This is the second notable marijuana-growing haul for the department in recent years. Richard Marriott was arrested after a vehicle crashed into his Ellicott City home in December 2010, killing the driver, setting the house on fire and also revealing that rooms in his home were being used to grow the drug. Twenty large plants and what police called sophisticated growing supplies were seized.
Last year, Marriott was sentenced to five years in prison, with all but six months of that sentence suspended and the sentence served as home detention.
"We do see this sort of thing in any county in the state, and probably throughout the country, so we're realistic that it does exist," Llewellyn said. "Our role is to identify where it's happening and appropriately arrest the people who are conducting illegal activities."
Baltimore Sun reporter Justin Fenton contributed to this article.