Shant Soghomonian, 35, entered the building in downtown Burlington on Friday and headed to Sanders’ office on the third floor. He was recorded by security cameras spraying a liquid near the door and setting it alight, the US attorney’s office said.

Sprinklers went off on multiple floors as Soghomonian departed via a staircase. There were several people inside the office but no one was injured, although the door and surrounding areas were damaged by the fire, the US attorney’s office said.

It was not immediately clear whether Soghomonian had a lawyer, and he could not be reached for comment.

Sanders is a long-serving independent in the US Senate representing the northeastern state of Vermont, although in 2016 and 2020 he unsuccessfully sought to become the Democratic Party’s presidential nominee.