PORTLAND — Portland made two separate drug trafficking arrests near the Sewall Street bus station over the weekend.

Shortly before 3 p.m. Saturday, a Portland officer was headed to the bus station when he pulled over a car after it ran a red light, police said. The driver, Leon A. Nelson, 32, of Boston, was found with 424 oxycodone pills that were not prescribed to him. Oxycodone sells illicitly for about $1 per milligram so the drugs would have been worth about $12,000 on the street, police said.

At about midnight that night, Portland police interviewed a man walking from the bus station. Police say Christopher Palmer, 22, of Gray was on probation and initially gave a false name. He was taken to Cumberland County Jail and as he was being processed there, turned over an ounce of crack cocaine, police said.

Maine Drug Enforcement Agency supervisor Sgt. Kevin Cashman said the Portland police arrests are part of an ongoing effort to stem the flow of illegal drugs into the state.