OAKLAND (KRON) — Boston police shot and killed a man Tuesday who they say had been under surveillance by terrorism investigators.

Police say that 26-year-old Usaama Rahim waved this large military-style knife when he lunged at officials Tuesday morning in the parking lot of a CVS drug store. Officials say he had been under 24-hour surveillance for as long as two years.

Police says that an FBI agent and a police officer identified themselves and confronted the man, but had no intention of any violence until they say Rahim pulled out the knife.

Rahim’s brother, Ibrahim Rahim, is an Iman at the Lighthouse Mosque in Oakland, where some members are calling Rahim’s death a murder.

The members of the mosque say that they are supporting Ibrahim Rahim. He posted on social media that his brother was killed while at a bus stop on his way to work.

Authorities think that Usaama Rahim had been radicalized by ISIS, and that they were also watching at least two of his associates.