ST. PAUL (AP) - The search for invasive Asian carp in the St. Croix and Mississippi rivers enters a new phase in the coming week.

The Minnesota Department of Natural Resources and other agencies will conduct a new round of environmental DNA testing, and this time it will include the Minnesota River.

Water samples will be drawn from 225 locations in the Mississippi and St. Croix and 50 on the Minnesota. They'll be tested for DNA from two Asian carp species, silver and bighead.

The process should begin Wednesday.

The Minnesota DNR recently completed a search for Asian carp in the St. Croix, using nets and electro-shocking gear, but got skunked. The testing followed tests that turned up silver carp DNA.

Officials say the failure to catch any suggests their numbers may be low.

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