Trayvon Martin's parent's Tracy Martin, left, and Sybrina Fulton, right, take part in the Million Hoodie March in Union Square on Wednesday.
A Manhattan church is calling for worshippers, clergy and choir members to wear hoodies on Sunday in honor of Florida teen Trayvon Martin.
The service at Middle Collegiate Church also will include a song composed in his memory.
The sermon will urge congregants to sign online petitions, and to post online photos of themselves and their friends wearing hoodies.
Trayvon Martin, 17, was walking home from a 7-Eleven in Sanford on Feb. 26 when he was shot by neighborhood watch volunteer George Zimmerman, who had called police and reported a "real suspicious guy" wearing a hoodie.
Martin was found dead, unarmed, with a bag of Skittles and an iced tea.
The case has drawn attention across the nation. President Barack Obama said Friday that he can't imagine what Martin's parents are going through, and said: "If I had a son, he'd look like Trayvon. I think they are right to expect that all of us as Americans take this with the seriousness that it deserves, and we're going to get to the bottom of what happened."
Zimmerman has not been charged in the shooting. He has said the teen attacked him and he shot him in self-defense.
On Wednesday night, demonstrators chanted "we want arrests" during what was called the Million Hoodie March in Union Square.
The teen's mother, Sybrina Fulton, told the crowd, "My heart is in pain, but to see the support of all of you really makes a difference."
Fulton also told the crowd her son's death was not a racial issue, but an issue of right and wrong. "Our son is your son," she told demonstrators.
The Department of Justice has opened a civil rights investigation and a local grand jury is set to meet next month to consider evidence in the case.
Police said Zimmerman is white; his family says he is Hispanic.
The march Wednesday was part of a social media event calling for Martin's supporters nationwide to upload photos of themselves wearing hoodies and use the hashtag #millionhoodies. See some of those photos here.
"A black person in a hoodie isn't automatically 'suspicious,'" says the event's Facebook page. "Let's put an end to racial profiling!"
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