A Pakistani doctor and former Mayo Clinic researcher has been indicted on one count of attempting to provide material support to a foreign terrorist organization after authorities say he told paid FBI informants that he pledged allegiance to the Islamic State group and wanted to carry out lone wolf attacks in the U.S.

The indictment against Muhammad Masood, 28, was announced Friday by U.S. Attorney Erica MacDonald. Masood was initially charged by criminal complaint and has been in custody since his March 19 arrest at the Minneapolis-St. Paul International Airport.

Prosecutors say Masood was in the U.S. on a work visa. They allege in court documents that from January to March, Masood made several statements to paid informants — whom he believed were members of the Islamic State group — pledging his allegiance to the group and its leader. He also expressed a desire to travel to Syria to fight for IS and carry out lone wolf attacks in the U.S., they said.

Masood messaged an informant “there is so much I wanted to do here .. .lon wulf stuff you know ... but I realized I should be on the ground helping brothers sisters kids,” according to an FBI affidavit.

Read more: AP News