An interagency task force of police descended on dozens of locations Thursday as they conducted the biggest drug raid in Clark County history, The Columbian reported.

According to The Columbian, about 300 officers from Southwest Washington and the Portland area were involved in the rolling sweeps that began at about 7 a.m.

More than 50 locations were targeted, the paper said.

Police told The Columbian that Asian drug cartels had rented homes in Clark County and used them to grow marijuana which has been sold throughout the U.S.

Police activity is expected to continue throughout the day.

The Columbian said even before today’s sweeps that 150 pounds of marijuana had been seized.

“The massive scale of this marijuana growing operation is staggering and unprecedented in the history of Clark County,” Commander Mike Cooke of the drug task force said in a news release.

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