Police responded to alarm at the home on Narrow Lane in Woodmere at 1:30 p.m. on Tuesday.
When police arrived, the son of the homeowners was in driveway.
Police asked him for ID. He showed them a credit card. They said that wasn't correct ID.
So, the 53-year-old man went into the house. As he opened front door, police got overwhelming smell of pot. Police opened up the door and saw tons of pot plants. They also spotted a semi-automatic handgun and two Vietnam era hand grenades. Police say they believe the hand grenades are extremely dangerous.
The man was taken into custody. He didn't resist arrest but did get agitated when police went inside the home.
ATF and the FBI have been working hours to disable the grenades. They also sent in robots and have gone inside the home wearing special suits.
About 20 residents were evacuated from the neighborhood and remained evacuated into the night Tuesday.
Neighbors say that the owners of the home are an elderly couple who winters in Florida. That's where they are now. They say they are a "very nice" couple.
Officials say the find is not terrorism related.
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