On a November afternoon last year, Andrew Poole gunned down a man who he thought had snitched to police about a playground shooting six weeks earlier in which a toddler and another man were injured, a prosecutor told a Common Pleas jury yesterday.

As Tremayne Walker, 30, bled to death on an Overbrook street, he told people, "If I die, Andrew Poole did this," Assistant District Attorney Richard Sax said in his opening statement at Poole's trial on murder, attempted murder, aggravated-assault and witness-intimidation charges.

Authorities have said that Poole, 23, of 61st Street near Columbia Avenue, Overbrook, mistakenly believed that Walker had snitched on him about a Sept. 24, 2007, shooting at Tustin Playground, a block from Poole's home.

On that day, Poole sneaked into the playground and fired an Intratec Tec-9 semiautomatic pistol 12 times in an attempt to kill Carl Wallace, 31, Sax said. Wallace, hit seven times, was critically injured.

Meanwhile, two stray bullets hit 18-month-old Mehkee Gatewood in a foot and an elbow, as the boy sat in a stroller with his twin brother. The toddlers' father, also there, was Wallace's friend.

Sax told jurors that "this case never was, never will be a whodunit."

But defense attorney Evan Hughes countered in his opening statement that the "evidence will show it was not my client who did these horrible things." Hughes contended the case "has many, many holes in it."

Yesterday's opening day of the trial focused on the slaying of Walker, a promising Christian-rock musician, on Nov. 11, 2007.

Walker was the lead singer-songwriter of the Christian-rock band Browne Boyz and had been set to sign a deal with Nashville-based Fervent Records, his family and friends have said.

Yesterday, three witnesses testified that when they ran up to a bleeding Walker at 61st and Oxford streets, Walker identified Poole as the shooter by his full name or his nickname, Drew.

Alice Holmes was in her house when she heard four or five gunshots. After she ran outside, she asked Walker who had shot him.

"He said Drew," Holmes testified. "I said, 'Who?' . . . He said, 'If I die, Andrew Poole shot me.' "

The next day, she said, a young man confronted her in her back yard while she was taking out her trash. He asked if she knew the person who was killed, tried unsuccessfully to find out where the victim lived, and threatened her by saying, " 'You know what happens to people who give up information? They get served,' " Holmes testified.

When Holmes returned to her house, she said, she saw a picture of someone who looked like the man "who just threatened me." Her daughter, a police officer, had her jacket on a sofa, and next to it was the picture, Holmes said.

After Holmes told her daughter what had happened outside, her daughter encouraged her to give another police statement. In the second interview, Holmes picked Poole out from a photo array.

Police Officer Robert Saccone likewise testified that when he responded to the scene, he asked Walker who had shot him. "The male responded, 'Drew Poole got me,' " he said.

Saccone said that another man at the scene, Terell Watson, also said that Walker told him that if he died, "Drew Poole shot me."

Police Officer Michelle Proctor, who was off duty at the time, testified that she was driving on 61st Street when she saw Walker. She stopped, went to his aid, and heard him say "Drew" shot him.

Police Officer Michael Maresca of the Crime Scene Unit testified that nine fired cartridge casings were recovered on 61st Street, and that a couple of projectiles flew into parked cars, while one landed in a nearby house.

The trial continues today before Judge Jeffrey Minehart.