Local police responding to a report of drugs inside a Nassau County home on Tuesday afternoon stumbled across something even more sinister — several explosive devices.

The FBI later arrived with a bomb disposal unit. Approximately 20 homes were evacuated out of precaution, police said.

Agents at the scene on Narrow Lane in Woodmere found explosive devices described as likely a pipe bomb and a grenade along with other weapons inside the home.

Officials say it is not terrorism related.

One person is in custody according to a law enforcement source.

Police were initially called to the home at 1:30 p.m. Tuesday to respond to some type of house alarm.

(Source: WABC)