LOS ANGELES (CBS/AP) — Officials say construction crews have completed work on the 405 Freeway ahead of schedule and have reopened all northbound lanes through the Sepulveda Pass.

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On Saturday, the closure of three of five lanes between the Montana Avenue and Getty Center exits snarled traffic for miles in West Los Angeles.

All lanes were reopened just after midnight Sunday, some 29 hours ahead of schedule.

The Los Angeles Metropolitan Transportation Authority said the lanes were supposed to close through 5 a.m. Monday.

The freeway was shut so crews could move the center median, repave and restripe a 2.4-mile stretch of the 405 as part of a $1 billion widening project, which KNX 1070’s Ed Mertz reports is two-thirds complete.

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“This is like performing open heart surgery on a freeway that’s still being used on a daily basis to move hundreds of thousands of people,” said Metro spokesperson Dave Sotero.

Sotero says construction crews are expected to transition their work from the side arteries to implanting the new lanes.

“Moving forward more of the work will be done on the actual freeway itself. For the last three years, we have been doing utility relocation work, building the underpasses, widening the underpasses, building retaining walls,” he said.

The reconstruction project remains more than a year away from completion.

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