"We got him, that's the main thing," Police Commissioner Charles H. Ramsey said Sunday as he stood outside Deliverance Evangelistic Church at 20th Street and Lehigh Avenue.
Less than an hour earlier, Ramsey and Mayor Nutter had stood at the head of a line of hundreds of uniformed police officers who had taken part in a memorial procession that ended at the church.
Ramsey said he learned of McFarland's apprehension as he waited to enter the church Sunday afternoon.
Clark said two detectives from his unit were scheduled to catch a plane Sunday night for Montgomery and begin the process of returning McFarland to Philadelphia. McFarland is also wanted on unrelated robbery charges, he said.
Police had been in contact with McFarland's family in Philadelphia, Clark said, and had gotten strong indications that he was in Alabama, where he has other relatives.
Family members were apparently able to persuade McFarland to turn himself in.
Authorities allege that McFarland and Rafael Jones, 23, of North Philadelphia, killed Walker during a botched robbery attempt around 6 a.m. Aug. 18.
Walker, a 19-year police veteran, had just finished a shift in the 22d District and was walking home when he was gunned down on Cecil B. Moore Avenue near 20th Street.
Authorities allege that Jones fired the three shots that killed Walker.
Jones was taken into custody on Wednesday and admitted his role in the killing Friday, according to police.
McFarland, of 23d Street near Master, was identified as the second suspect late last week.
Nutter said that before the start of Sunday's ceremony, he had told Walker's mother that "we would get the other suspect."
Clark said police would provide the District Attorney's Office with evidence to support a murder charge against McFarland once he is returned to Philadelphia.
Nutter, who praised police for a quick and thorough investigation, appeared convinced that both suspects were guilty.
"Both should rot in jail for the rest of their lives," the mayor said, "and rot in hell after that."
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