The couple accused of stabbing Johns Hopkins researcher Stephen Pitcairn to death as he walked home along St. Paul Street last month is scheduled to be arraigned on murder, assault and robbery charges Sept. 24.

A city grand jury indicted Lavelva Merritt, 24, and John A. Wagner, 34, both of the 2600 block of Maryland Ave., last week, the Baltimore State's Attorney's Office announced over the weekend. They have been held without bail since late July.

Pitcairn, 23, had visited his sister in New York and was walking home from Penn Station to his Charles Village apartment July 25, about 11 p.m. He was talking to his mother on his cell phone when two robbers, alleged to be Wagner and Merritt, demanded cash and stabbed him in the chest. He died in the arms of an area resident who heard the commotion.

Witnesses claim they Wagner and Merritt boasted about the crime, and the couple was arrested within 24 hours of Pitcairn's death. Bloody shoes, a wallet and Pitcairn's iPhone were found in their home, according to charging documents.

tricia.bishop@baltsun.com