One suspected robber has been arrested, but investigators still are searching for the alleged accomplice who they identified after examining a cell phone that was left at the scene of a robbery last month in Derry Township.

Dion Richherd Ford II, 19, of Derry, is a primary suspect in the Jan. 26 robbery of the Choice Convenience Store on Route 217 in the township, according to a police affidavit.

Investigators said Mr. Ford entered the store while another suspect, Reed Moore, 21, of Derry, remained outside as a lookout.

In this early morning robbery, Mr. Ford jumped the counter and struggled briefly with the woman working as a clerk, police said.

The woman told police both suspects repeatedly threatened to kill her if she did not cooperate.

Mr. Ford took $1,863 from the store safe before he and Mr. Moore fled, police said.

The number recovered from the cell phone is that of Mr. Ford, police said.

A search of the phone's files revealed the suspect had sent and received a number of text messages from his girlfriend, Sharonda Stewart. The couple live together at a residence in Dogwood Acres "a few hundred feet" from the store, the affidavit said.

Ms. Stewart told police that Mr. Moore, driving a Lincoln Continental, picked up Mr. Ford around 3 a.m. About an hour later, she said, Mr. Ford sent her a message that he and Mr. Moore were going to rob the store, the affidavit said.

When he returned home, the affidavit said, Mr. Ford told his girlfriend that he had lost his cell phone and told her to have the service disconnected.

Police said the two suspects, after the robbery, went to the home of Matthew Rosenberger in Latrobe, where they were overheard discussing the robbery and that Mr. Ford had lost his phone in the process.

Mr. Rosenberger said the two suspects laughed about Mr. Ford having left his cell phone at the scene.

Mr. Ford, who had been seen in surveillance video wearing a hooded sweatshirt, left the garment at Mr. Rosenberger's residence. It was turned over to police.

The video also showed the suspect's cell phone on the floor in front of the store safe, the affidavit said.

Mr. Moore was arraigned Tuesday before District Judge Mark J. Bilik on charges of robbery, making terroristic threats, theft, simple assault, receiving stolen property and two counts of conspiracy. Police said they were able to find him based on text messages and numbers obtained through the cell phone.

He was released on a property bond yesterday from the Westmoreland County Prison, and he is awaiting a preliminary hearing.

Mr. Ford still is being sought, police said.

Anyone with information on his whereabouts can call state police at 724-832-3288.

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