Don't worry, folks. An explosion inside the Metrodome that prompted calls to Minneapolis police wasn't accidental and didn't damage anything it wasn't supposed to destroy.

Crews working on the demolition of the 31-year-old stadium detonated a dozen or so charges simultaneously, severing the roof support cables and causing the final roof structure to fall to the stadium floor.

Mortenson Construction said before the blast that it expected minimal disturbance in terms of noise, vibration and dust.

"For comparison, the detonation will have a slightly lower decibel level than the pyrotechnics used following a Vikings touchdown," ESPN reported on its website Sunday.

The crews didn't, however, alert the general public, thus prompting at least a half-dozen or so calls to police asking what was going on.

The detonations did cause temporary street and sidewalk closures from 5:30 to 8 a.m. Sunday, and Metro Transit light rail was delayed for a brief time since there was no public access permitted within 250 feet of the stadium.

The dome is being erased from the Minneapolis skyline to make way for a new $1 billion Vikings stadium. The Teflon-coated roof took about 35 minutes to deflate on Jan. 18.

By April, the entire structure should be gone. Steel installation for the new stadium is expected to begin in August. The roof installation will begin in the fall of 2015 and by the end of next year, the new stadium will be fully enclosed with heating.

The new stadium is slated to open in July 2016.

The Vikings also plan to open a new stadium Preview Center next month. It will be located in an office building at 1010 S. 7th St., and will hold some sales and marketing staff as well as a "mock-up suite" of the stadium, according to the Minneapolis-St. Paul Business Journal.

The Minnesota Sports Facilities Authority and Mortenson Construction will also lease space in the building, the Journal reported.

Pat Pheifer • 952-746-3284