EDISON - Police say the man who fired shots inside a mall last year before killing himself was under investigation for selling drugs.
Hackensack police released the information about Richard Shoop yesterday along with details of a large-scale drug sweep in northern New Jersey.

Investigators say Shoop had sold MDMA to an undercover officer 10 days before he opened fire inside the Garden State Plaza in Paramus last November. No one else was hurt. 

Police say a note found after the shooting indicated Shoop knew he was under investigation.
Hackensack Police Director Michael Mordaga says Shoop had also been arrested six months earlier for selling the pure form of ecstasy, known as "Molly." Mordaga also says Shoop had the hallucinogenic drug in his system during the shooting, according to toxicology reports.

Investigators say Shoop was part of a larger drug ring from which 160 suspected drug dealers have been arrested after a seven-month undercover investigation.

Among those arrested was a convicted murderer and sex offender who police say sold drugs to an undercover officer on three separate occasions. During the investigation, police learned that Charles Williams was involved in the stabbing of a 24-year-old man earlier this month. He was charged with aggravated assault.

At an arraignment today, authorities said their investigation uncovered information that they believe could link Williams to three other cold case child murders.