Statham noted that the clergy group represented POWER - Pennsylvanians Organized to Witness, Empower, and Rebuild - a broad spectrum of churches committed to social justice.
She said about 1,000 clergy are expected to march in Clayton, Mo., to the St. Louis County prosecutor's office. "Our prayer is that their message is about peace," Statham said.
The Rev. Mark Kelly Tyler, pastor of historic Mother Bethel A.M.E. Church and a member of POWER, said in a telephone interview Wednesday that he and some of the clergy from Philadelphia were caught in the unrest between police and protesters Monday when they arrived in Ferguson.
"We got teargassed and [were hit by] shock grenades. We just happened to walk out Monday night with our clergy collars on. Everybody in the crowd got teargassed," Tyler said.
He said he and other clergy, including Royster, the Rev. Ernie Flores of Second Baptist Church of Germantown, the Rev. Leslie Callahan of St. Paul Baptist Church in North Philadelphia, and the Rev. Cean James of Faith Christian Fellowship in West Philadelphia, went to Ferguson as members of Philadelphia's POWER contingent.
Brown, 18, who is black, was killed Aug. 9 by Darren Wilson, a 28-year-old white officer, after being stopped on a street, officials said. An autopsy indicated that Brown was shot six times.
The shooting has sparked 10 days of protests and as many nights of unrest.
Tyler said Wednesday that clergy from around the country were planning a major protest march for Thursday. "We're calling for 1,000 clergy to walk with us to march to the local prosecutor's office," Tyler said. He said plans include calling for an indictment against Wilson.
Tyler said the clergy were also considering a potential act of civil disobedience. "We're talking right now about the possibility of walking back into Ferguson in a way that would actually lead to the arrest of some clergy to bring attention to the fact that this indictment has yet to come down and also to demonstrate against what we feel is excessive action on the part of law enforcement," Tyler said.