SOUTH BAY (CBSLA.com) — A well-known pastor in the South Bay has died unexpectedly, it was reported Friday.

Rev. Stephen Mays of Calvary Chapel South Bay passed away Thursday from complications during back surgery.

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Mays was vocal about being a former gang member and former drug addict who turned his life around.

He took over the church in the 1970s, which had 75 members at the time.

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Membership has since grown to 9,000 parishioners.

One church official said, “This is a day of sadness.”

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Mays was 64 years old.