At least four other core members, including one leading member of the group who uses the handle Sabu, have yet to be detained.

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One out of every four people in town is a dues-paying member of a group called Friends of the Fossil Library.

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Mr. Mabao was 16 when he started guiding tourists up Mount Mayon and is a member of the Panaway Mountaineer Group, which usually climbs the 2, 440-metervolcano three to four times a week.

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