MINNEAPOLIS — A remaining ring beam that made up part of the Metrodome’s roof structure has been taken down using controlled explosives.

Officials set off a series of charges Sunday about 7:30 a.m. Within seconds the roof ring fell and several walls collapsed in a cloud of dust.

The 32-year-old facility was being demolished last week, but officials halted work after one part of the ring beam fell out of sequence.

After consulting with structural and demolition experts, the Minnesota Sports Facility Authority recommended bringing down the remaining portion of the ring beam with controlled explosives.

Contractors did so using 84 charges of dynamite in 24 columns of the upper concourse.

The public wasn’t allowed within 250 feet of the site, and the nearby light-rail station was closed during the demolition.