Police say two California teenagers used a prescription sleeping medication to spike the milkshakes of too-strict parents so they could log onto the Internet.

The parents called police and the 15-year-old Rocklin girl and a 16-year-old friend were taken to Juvenile Hall. Rocklin is 20 miles northeast of Sacramento.

The Sacramento Bee reports the girls offered to pick up milkshakes at a fast-food restaurant for the parents of one of the girls on Friday night.

The drug was mixed into the shakes and the couple fell asleep. The suspicious parents picked up a drug test kit the following day.

The girls told investigators they wanted to use the Internet, which was shut down daily at 10 p.m.

It’s unclear what the girls did on the Internet.