Police say the suspects took a small amount of marijuana and some cash, before leaving the clinic in a tan late-model Nissan Titan pick-up truck.
"They were very calm and meticulous and there was no panic on their part," said Det. John Doerbecker of the /*Los Angeles Police Department*/.
The victims are still in intensive care at a hospital.
The suspects could face robbery and attempted murder charges.
Anyone with information on their whereabouts is urged to call Los Angeles police at (877) 527-3247.