STUDIO CITY (CBSLA) — Police in the Inland Empire stumbled upon a pot grow operation inside a homeless encampment in the Santa Ana riverbed.

Officers were on a call for a report of someone waving a firearm north of Martha McLean-Anza Narrows Park near Jurupa Valley, Riverside police announced in a press release Tuesday.

Authorities say they discovered about 30 large marijuana plants, "many over 10 feet tall and with a combined weight of approximately 500 pounds."

Police said the area was booby-trapped and that several weapons were found. Two people were detained and later released pending an investigation.

The original suspect thought to have a gun was never found.

The agency estimated the the drugs' street value at tens of thousands of dollars.