John F. Kennedy High School in the Bronx will not be ready for Sept. 9 opening following gas line explosion

BRONX, N.Y. (WABC) -- Work to repair a New York City high school after a gas line exploded during construction Thursday will not be completed by the time school begins in a few weeks.

School is supposed to begin at John F. Kennedy High School on Sept. 9. The school, located in the Marble Hill section of the Bronx, serves more than 1,200 students in grades 9-12.

Friday morning, workers were assessing the structural integrity of the Terrace View Avenue building.

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Mayor Bill de Blasio said alternative arrangements are being made.

"We are now going to work to make sure every student has a good and appropriate place for school," de Blasio said. "The JFK Building will not be re-opening by opening day of school, there will be more work to be done."

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Officials said the important thing is that students are in a safe place for school.

The explosion on the sixth floor Thursday night injured three construction workers and caused significant damage to three floors of the building.

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One of the workers injured is in critical condition, and the two others are in serious condition.