EAGLE, Colo. (CBS) – Chicago hiker James Nelson has been gone for a week in the mountains of Colorado, and there is still no word on him.

The search for Nelson resumed Monday morning. The Eagle County, Colo., sheriff’s office said a search and rescue effort for Nelson began Saturday.

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Nelson, 31, set out on a five-day hike of Mount of the Holy Cross near Vail on Oct. 3. His fiancée reported him missing Friday evening.

The Colorado National Guard is dropping search teams and conducting an aerial search on the mountain, which is one of the best known of Colorado’s 14,000-foot peaks.

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James is an experienced hiker and is equipped with proper gear and supplies. But authorities say he is not carrying a cell phone.

The search wrapped up Sunday evening and was scheduled to pick up again at dawn Monday.

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