Woman arrested in Kansas City allegedly had 8 pounds of fentanyl

An 18-year-old California woman was charged Tuesday by federal prosecutors in Kansas City with possession of 8 pounds of fentanyl.

Esmeralda Castro, of San Bernardino, was arrested Monday after a drug-sniffing dog detected the presence of drugs in her luggage at a Kansas City bus station, according to documents filed in U.S. District Court in Kansas City.

Castro told investigators she was carrying the bag to New York for her boyfriend and was supposed to meet someone there, and then return with $1,500 to deliver to her boyfriend, according to the documents.

Fentanyl is a synthetic opioid used to treat severe or postoperative pain.

It is reportedly 50 to 100 times more potent than morphine and is often used by drug abusers in a mixture with heroin or cocaine.

Those drug combinations have been blamed in part for a spike in overdose deaths across the country.

This story was originally published May 9, 2017 at 4:18 PM with the headline "Woman arrested in Kansas City allegedly had 8 pounds of fentanyl."