The Newark Archdiocese has told North Jersey pastors and Catholic school officials that holding Ice Bucket Challenges, a wildly popular fad that has raised millions of dollars to combat a crippling illness, conflicts with church teachings by funding embryonic stem-cell research.

The warning was issued Thursday in a letter from a church official and with the blessing of Archbishop John J. Myers. It said some of the research funded by the ALS Association, which receives much of the money from the Ice Bucket Challenge, involves embryonic stem-cell research, which is opposed by the Catholic Church because of conflicts with its antiabortion mission.

The challenge involves dumping ice water on participants' heads and donating money for research into ALS, or amyotrophic lateral sclerosis, also known as Lou Gehrig's disease. The Rev. Lawrence Fama, director of the archdiocesan Office of Respect Life, called the challenge "a stunt" that can be "fun and engaging," but questioned whether the practice conflicts with "Catholic moral teaching."

The archdiocese sent the letter Thursday to principals at all 94 Catholic schools in the archdiocese, and to pastors and religious education staff at 218 parishes. It suggested sending donations to organizations that don't use embryonic stem-cell research.