groups_ban_member( int $user_id, int $group_id )

function groups_ban_member( $user_id, $group_id ) {

	if ( ! bp_is_item_admin() )
		return false;

	$member = new BP_Groups_Member( $user_id, $group_id );

	/**
	 * Fires before the banning of a member from a group.
	 *
	 * @since BuddyPress 1.0.0
	 *
	 * @param int $group_id ID of the group being banned from.
	 * @param int $user_id  ID of the user being banned.
	 */
	do_action( 'groups_ban_member', $group_id, $user_id );

	return $member->ban();
}