By Brad Segall

RIDLEY PARK, Pa. (CBS) — Authorities in Delaware County have arrested two people in connection with a hit-and-run crash in Ridley Park in April that critically injured a teenager riding his bicycle.

After an intense, ten-week investigation that covered three states, police have arrested 25-year-old Adrienne McCrea and her 31-year-old boyfriend, Ty Winsheimer.

Police say McCrea was behind the wheel of the truck that struck 18-year-old Christopher Brooks on Chester Pike (see previous stories).

Delaware County DA Jack Whelan says they have witnesses who can place McCrea in two separate bars that night, but because she fled they can’t say for sure if she was drunk at the time of the accident.

“We believe that obviously is the motive for her to flee and to go to such great extent to cover up this accident,” Whelan said today.

Winsheimer told police he helped cover up the crash by hiding the truck in New Jersey and then selling it to a junk dealer in Virginia.

Brooks, the bicyclist, had to have part of his leg amputated and suffered a brain injury.  He continues to recover.