Friends of Rebecca Robison are planning to hike several Windward O'ahu trails today in search of the missing Kailua woman.

Robison, 25, has not been seen since noon Wednesday after mentioning to friends she was going hiking that day. Police did a helicopter search Saturday but found no trace of Robison.

Morgan Cooper, a friend of Robison, said a second search is planned Saturday if today's effort is unsuccessful. The plan today is to cover five trails today over a four- or five-hour period, Cooper said.

Anyone interested in joining the search group today should go to one of two meeting locations: the parking lots of Central Union Church, 1660 S. Beretania St., at 7:45 a.m. or Don Quijote in Kailua, 345 Hahani St., at 8:30 a.m.