Concerned Detroiters spoke out against medical marijuana shops at a public hearing Thursday night and pleaded with city officials to implement new regulations to stifle the industry's growth.

"There's some way we have to control it because this is like an invasion," longtime Detroit resident Nancy Bitzarakis said at the hearing.

Bitzarakis was among several residents who spoke at the city Planning Commission's hearing at a near-capacity city hall auditorium, with most supporting a crackdown on the marijuana dispensaries. Residents described an ever-increasing number of dispensaries opening up near their neighborhoods, inviting undesirable activities -- people smoking joints in parking lots, for example -- and an atmosphere damaging to children.

Several marijuana advocates also attended the meeting to remind city officials about the substance's medical benefits.

Marcea Bright, 41, said she was diagnosed with breast cancer two years ago and relies on medical marijuana for pain relief, nausea and sleep deprivation. Bright said she...