MINNEAPOLIS - Administrators at Minnehaha Academy say the start of classes for some students will be delayed about two weeks after an explosion and partial building collapse killed two people Wednesday.

In a memo to parents, Minnehaha Academy President Donna Harris says the start date for the damaged Upper School will likely be postponed from Aug. 23 to Sept. 5.

"We have felt the power of your prayers as we mourn together, recognizing that God will be our comfort, strength, and guide in the days, weeks, and months to come," Harris said in the letter.

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The academy's Upper School houses the high school. The Lower and Middle Schools campus is about a mile and a-half away and was not damaged in Wednesday's blast.

A team from the National Transportation Safety Board arrived in Minneapolis Thursday to begin the painstaking task of determining what caused the natural gas explosion.

Harris said as agencies work to assess the Upper School building and determine its structural soundness, they are looking into their options.

"We don’t know how long this assessment will take, but we are actively considering viable solutions to ensure we are able to provide academic programming for our Upper School students," she states.

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There will be no change to the Upper School athletic schedule, according to the memo. Sports will begin Monday, Aug. 14.

"We have been overwhelmed by your support, and your offers of help," Harris wrote. "Please know that we will reach out to you when those opportunities are clear. My prayer is that we will lock hands and hearts and do the hard work of rebuilding together."

Minnehaha Academy said on its Facebook page that the school will hold a service Sunday at 6 p.m. for John Carlson, the 81-year-old custodian killed in Wednesday's blast, in the lower and middle school chapel. The school says Carlson's family will receive visitors before the service beginning at 4 p.m.

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