JERSEY CITY -- Twelve of the city's "most violent offenders" were arrested yesterday after police investigated ongoing violence between two rival gangs, a city spokeswoman said.

The men, all between the ages of 18 and 31, were arrested during an early morning operation that concluded a five-month-long investigation, Jersey City spokeswoman Jennifer Morrill said.

The arrests were a joint operation between the Jersey City Police Department's Street Crimes Unit, Major Case Squad, Cease Fire Unit, and Criminal Warrants Squad, as well as the Hudson County Sheriffs Department, the Hudson County Prosecutor's Gang Unit, New Jersey State Police, and the United States Marshals.

"This operation combined traditional policing techniques along with innovative technological advancements in an attempt to dismantle the gangs' leadership and damage its ability to illegally sell narcotics and weapons," Morrill said in a statement.

Morrill did not include the names of the two rival gangs, but provided the general areas both are located. One of the groups operates on Martin Luther King Drive between Warner Avenue and Armstrong Avenue, on Bostwick Avenue between MLK Drive and Ocean Avenue, as well as the area around Muhammed Ali Park, Morill said.

The other gang operates from Arlington Park to the intersection of Harmon Street and Randolph Avenue, and down Communipaw Avenue to the area surrounding Van Horne Street, Morrill said.

Since the launch of the investigation, 134 gang-related arrests have been made, along with the recovery of 14 illegal guns and large quantities of drugs, Morrill said.

Jersey City saw a number of violent crimes committed between October and November. Seven people were shot to death in the city's west and south districts during the two-month span -- which included five fatal shooting over the course of 12 days.

Officials expect more arrests as part of the investigation. Charges from yesterday's arrests include gang criminality, conspiracy to commit aggravated assault, weapons and drug offenses.

The 12 people arrested are:

Daquan Edwards, 19, of Van Nostrand Avenue. He is charged with gang criminality

Rashaun Bell, 19, of Princeton Avenue. He is charged with gang criminality

Frederick Barnett, 19, of Bostwick Avenue. He is charged with gang criminality.

Stefan Alexandre, 21, of Seaview Avenue. He is charged with unlawful possession of a weapon and possession of a weapon by a minor.

Frederick Thomas, 21, of MLK Drive. He is charged with conspiracy to unlawfully possess a weapon and possession of CDS.

William Conyers, 21, of Wegman Parkway. He is charged with gang criminality and conspiracy to commit aggravated assault.

Kenny Harrigan, 19, of Clerk Street. He is charged with conspiracy to unlawfully possess a weapon.

Rafael Gomez, 18, of Summit Avenue. He is charged with conspiracy to unlawfully possess a weapon and possession of a firearm by a minor

Samuel Washington, 27, of Myrtle Avenue. He is charged with gang criminality

Gerald Hagood, 20, of Pearsall Avenue. He is charged with conspiracy to possess CDS.

Laquan Clark, 31, of Woodlawn Avenue. He is charged with three counts of conspiracy to unlawfully possess a weapon, gang criminality, conspiracy to possess CDS, conspiracy to possess CDS with the intent to distribute, possession of CDS, possession of CDS with intent to distribute, and possession of CDS within 1000 feet of a school.

Jamie Franklin, 20, of Dwight Street. He is charged with gang criminality, conspiracy to possess CDS with the intent to distribute, six counts of conspiracy to unlawfully possess weapons, six counts of conspiracy to commit robbery, four counts of conspiracy to possess CDS, and conspiracy to commit aggravated assault.