Top Iranian nuclear scientist Mohsen Fakhrizadeh was laid to rest Monday after his assassination by what a security official in the Islamic Republic claims was a team of Israelis who used remote “electronic devices,” according to reports.

Axar.az reports citing foreign media that Ali Shamkhani, secretary of the Supreme National Security Council, made the allegation at Fakhrizadeh’s funeral, where Iran’s defence minister also vowed to continue the man’s work “with more speed and more power.”

“Unfortunately, the operation was a very complicated operation and was carried out by using electronic devices,” Shamkhani told state TV. “No individual was present at the site.”

He also blamed Iranian exile group Mujahedeen-e-Khalq for “having a role in this,” without elaborating. The MEK did not immediately respond to a request for comment.