A medical call to a home in southwest Atlanta on Sunday ultimately leads to a marijuana grow house.

Atlanta Police Officer John Chafee tells WSB they were called to a home on Telford Terrace for a medical emergency, but quickly determined they should also investigate a nearby house after noticing a strong smell coming from it.

"When I pulled up, it was immediately noticeable when I got out of the vehicle.  When officers responded to the area for another call at a nearby residence, they were able to notice this odor.  It was strong enough for them to notice from outside," said Chafee.

Investigators knocked on the door and when they didn't get a response, police returned to the house on Monday with a search warrant.

"Upon serving the search warrant, they located a large grow operation, marijuana grow operation, inside of the home," said Chafee.

A minimum of 250 plants valued at $500,000 were discovered.  Chafee says it appears that this operation was broken up into about four rooms based on the size of the plants.

Police are getting ready to issue arrest warrants.