SPRINGFIELD - State and local police, executing search warrants in Springfield and West Springfield Tuesday, arrested 11 suspects and seized 6,700 bags of heroin.

Hampden District Attorney Anthony Gulluni announced the arrests and disruption of what he described a "high level" heroin trafficking operation, during a press conference at his office at 1500 Main St.

One of the search warrants was executed at U Name It Self Storage, Unit WS-14, at 203 Circuit Ave, in West Springfield. Police seized a 2006 BMW there along with $25,380 in cash. In all, 12 warrants were executed, Gulluni said.

Police also seized approximately $48,000 in cash, two other vehicles and three handguns, "all of which were loaded at the time they were seized by police and in a position ready to fire,"Gulluni said.

The Tuesday arrests followed a months-long investigation that involved "electronic surveillance of various kinds, sophisticated surveillance techniques and hundreds of man-hours," Gulluni said.

Those arrested are all Springfield residents. Their names, the locations where they were arrested and the items seized are as follows:

Derek-Lopez, 30, was arrested at 145 Cambridge St. and charged with conspiracy to violate drug laws. Police seized 9 bags of heroin and approximately $7,164.

Milagro Ortiz, 48, and Kevin Rivera-Ortiz, 20, were arrested at 29 Morris St. Both were charged with conspiracy to violate drug laws and trafficking in heroin (36-100 grams). Rivera-Ortiz was also charged with possession of a loaded firearm with an FID card, possession of ammunition without an FID card.

Police seized one loaded Glock .40 caliber handgun, 19 .40 caliber rounds of ammunition, approximately $460 and 1,400 bags of heroin (all packaged for distribution).

Efrain Rosario, 22, and Jean Rosario, 20, were arrested at 29 Windsor St. Both were charged with conspiracy to violate drug laws, trafficking in cocaine (100-200 grams), possession of a loaded firearm without an FID card and possession of ammunition without an FID card.

Police seized a Glock 9 mm handgun, 16 rounds of 9 mm ammunition, heroin packaging and processing paraphernalia and approximately $6,113.

Kenen Monsanto-Maldonado,18, and Matthew Carasquillo, 21, were both arrested at 405 Cherry St. Both were both charged with conspiracy to violate drug laws. Monsanto-Maldonado was also charged with trafficking in heroin (100-200 grams) and Carasquillo was also charged with possession of heroin with intent to distribute.

Police seized approximately 550 bags of heroin.

Cassandra Cardona, 21, was arrested at 19 Layzon Brothers Road. She was charged with conspiracy to violate drug laws, trafficking in heroin (over 200 grams), possession of heroin with intent to distribute.

Police seized approximately 9 grams of raw uncut heroin, an Infiniti M37 and approximately $760.

Fabian Haddock-Ortiz, 28, was arrested at 47 Beacon Terrace and charged with conspiracy to violate drug laws, trafficking in heroin (36-100 grams) and possession of ammunition without an FID card.

Police seized 1,500 bags of heroin, 15 rounds of miscellaneous calibers of ammunition, 10 grams of raw uncut heroin and $4,395.

Joshua Rosado, 20, was arrested at 24 Wilcox St. He was charged with conspiracy to violate drug laws. Police seized a .40 cal. 20-round clip, a bag of cocaine and a Jeep.

"I would like to thank the dedicated and professional members of law enforcement who participated in this investigation," Gulluni said. "Continuing to hold accountable those who wish to profit from addiction remains the number one priority of my administration."

The investigation was conducted by the Hampden County Narcotics Task Force, which consists of the state police detective unit attached to Gulluni's office, the Springfield Police Department's Narcotics, Street Crimes and C3 units, the West Springfield Police Department and Homeland Security Investigations.

This is a developing story. Additional information will be added as soon as it is available.