Authorities said the suspects entered the clinic at Roscoe Boulevard and White Oak Avenue at 9:40 p.m. At least one of them was armed with a weapon.
A gun battle occurred, as the clerks inside the facility also armed themselves. Two employees of the clinic were shot, and a pit bull was also shot and killed. Another dog was unharmed.
The suspects fled the scene in a gold SUV in an unknown direction. Police are unsure if anything was taken from the marijuana clinic.
The victims were rushed to a local hospital, where they remain in critical condition.
Police hope surveillance images will help them solve the crime.
The gun battle that erupted in Northridge is just the latest violent incident tied to medical marijuana facilities. Over the summer, two other clinics were hit, and two clinic workers ended up dying in those incidents.
The two murders happened on the same day just a few miles apart. Two workers were shot at the Higher Path clinic in Echo Park, and one victim died. A few hours later, a clinic worker at Hollywood Holistic was found dead.
The violence has those living and working near the clinics wondering about their safety.
"We have people wandering, just walking by, and the ladies that work here, sometimes they're here probably till 9, so some of them don't feel so safe," said realtor Tracey Aguirre.
Anyone with information about the Northridge shooting is urged to call the LAPD West Valley Station at (818) 374-7611.