Several people are facing charges following a months-long investigation into suspected drug dealers operating in the Lower Mainland.

New Westminster police announced Monday that "numerous" people have been arrested – officers have not said exactly how many – and the force will be recommending several charges against them. The charges include trafficking in a controlled substance and conspiracy to commit an indictable offence.

The arrests were the culmination of an investigation that began months ago, which started locally in New Westminster, but quickly developed into a case spanning much of the Lower Mainland.

NWPD worked with Surrey RCMP, Delta police, the Canada Border Services Agency, the Combined Forces Special Enforcement Unit and the Lower Mainland Emergency Response Team through the course of its investigation.

Through search warrants executed in Surrey and New Westminster, police said they seized a number of vehicles, firearms and replica firearms. They seized a "large quantity" of cash, and an amount of fentanyl-laced heroin and pure fentanyl with a street value of approximately $300,000.

The potent opioid has been at the forefront of B.C.'s overdose crisis, which claimed the lives of more than 900 people last year.

Numbers released last week suggest 2017 will also have a high death toll, with the province on a trajectory to hit more than 1,300 deaths this year. An estimated 400 of those are expected to occur in Vancouver alone, Mayor Gregor Robertson said.

Data from the BC Coroners Service suggested that 120 people died of overdoses in March, an average of 3.9 per day. The month, which was the third most deadly in B.C.'s history, saw a death toll up 52 per cent from March 2016. 

While the coroner has not said exactly how many of the deaths are specifically due to fentanyl, the latest report said fentanyl-detected deaths appear to account for the dramatic increase. The number of overdose deaths from drugs other than fentanyl has remained relatively stable for the last six years, at an average of 305 per year.

The coroner's report said the top three townships where fatal illicit drug overdoses occurred were Vancouver, Surrey and Victoria.