Iran said Tuesday it is building a sophisticated new building near its underground Natanz nuclear site, state TV reported.

The report quoted Ali Akbar Salehi, head of the country’s nuclear department, as saying the new structure is being built in the wake of a July explosion that damaged a building that housed centrifuge machines.

“Regarding the evil action and sabotage that was carried out, it has been decided to establish a more modern, vaster and inclusive (building) to be constructed in the heart of the mountains around Natanz,” Salehi was quoted as saying.

Last month, Iran said it found those who were involved in the alleged sabotage but said details will be released later.

Natanz hosts the country’s main uranium enrichment facility. In its long underground halls, centrifuges rapidly spin uranium hexafluoride gas to enrich uranium.

Salehi said construction of the new building “has already begun.”

Iran has said its nuclear site had not been operating at full capacity due to restrictions imposed by Tehran’s 2015 nuclear deal with world powers. Iran began experimenting with advanced centrifuge models after the United States unilaterally withdrew from the deal two years ago.

Iran has long maintained its atomic program is for peaceful purposes.

The International Atomic Energy Agency says Iran enriches uranium to about 4.5% purity — above the terms of the nuclear deal but far below weapons-grade levels of 90%. Workers there also have conducted tests on advanced centrifuges, according to the IAEA.

Source » nytimes