Several new charges have been laid against Jimmy Melvin Jr., recently charged with murder in the death of his former ally-turned-rival, and Halifax Regional Police say there may be more charges coming.

Security was tight at the Spring Garden Road courthouse on Monday as the 33-year-old Halifax man arrived with a blanket over his head.

A day earlier, Halifax police charged Melvin with first-degree murder and attempted murder in the February 2009 shooting death of Terry Marriott Jr.

Defence lawyer Pat MacEwan, who appeared in court on Melvin’s behalf, says his client is innocent of those charges, and the new drug- and murder-related ones laid Monday afternoon.

“He's upset that he's being accused of this and he maintains that he's not guilty of this and I expect we’ll be fighting this all the way through the court system,” MacEwan said.

Four drug-related charges were announced Monday, as well as the Crown’s intention to charge Melvin with conspiracy to commit murder.

“The attempted murder and the conspiracy to commit murder took place at the same time and place: December 2nd, 2008,” said Crown prosecutor Rick Woodburn.

Those charges stem from an incident investigators learned about during their investigation into Melvin, though police say it was never reported.

Because two or more people were involved in the alleged attempt to murder Marriott, police should have laid the conspiracy charge at the same time as the attempted murder charge, Woodburn said.

“It was just simply an oversight. I believe they just looked at the charges and laid that one, but the conspiracy charge is certainly there too,” Woodburn said.

There’s no indication of when the conspiracy charge will be filed, or how many people are involved in the alleged plot.

As for Melvin’s defence lawyer, he says it remains a non-issue for now.

“At this point in time, there is no conspiracy charge. It hasn’t been laid yet. There's been some talk of it and we’ve heard about it this afternoon. I haven't seen it,” MacEwan said.

Halifax Regional Police spokesperson Sgt. Pierre Bourdages said police are continuing their investigation and more charges could be laid against Melvin or others.

Melvin has been remanded into custody until his next scheduled court appearance on Sept. 8.

The Crown says they will oppose any form of release for him.

With files from CTV Atlantic’s Rick Grant