A request by the brother of an imprisoned leader of a polygamous sect to increase the water available to the group's compound in South Dakota is making landowners and law enforcement officers wary that the troubled church might be expanding.

Seth Jeffs, the brother of Warren Jeffs, says members of the Fundamentalist Church of Jesus Christ of Latter-Day Saints need more water for gardens, orchards and animal herds at their Black Hills spread.

Federal agencies cite environmental concerns, and several landowners have moved to intervene. Law enforcement officers say the move may signal that group plans to expand, after a Texas compound was seized and Utah authorities evict members from an enclave in the Southwest.

Seth Jeffs declined to comment. The water request will likely be decided on in May.