Two people are due in Lawrence District Court today on charges of allegedly trafficking 1 kilogram of cocaine that Andover police discovered Wednesday during a traffic stop.

Felipe Fernandes, 34, and Lidiane Brasileioro Fernandes, 24, both of Tewksbury, each were charged on one count of trafficking in more than 200 grams of a Class B substance, Andover police Chief Patrick Keefe said.

Andover narcotics detectives were conducting surveillance at 4 p.m. Wednesday on River Road when they saw “activity consistent with drug distribution,” Keefe said.

Detectives John Delaney, Michael Lane and Matthew Hughes stopped the suspicious vehicle they’d been watching and found about 1 kilogram of cocaine, the chief said.

Fernandes was arrested and held on $500,000 bail, Keefe said, and Brasileioro Fernandes was held on $150,000 bail.

The two are scheduled to be arraigned today in Lawrence District Court.