BOSTON (CBS/AP) – The family of the man killed by terror investigators in Roslindale earlier this week has hired two attorneys.

Usaamah Rahim‘s family said Thursday that it hired the lawyers “to ensure that a complete and transparent investigation into the circumstances” surrounding Rahim’s death occurs.

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Rahim was shot Tuesday after investigators approached him to question him about “terrorist-related information” and police say he lunged at them with a military-style knife.

Usaama Rahim was shot and killed by the Joint Terrorism Task Force in Roslindale, June 2, 2015. (WBZ-TV)

Usaamah Rahim was shot and killed by the Joint Terrorism Task Force in Roslindale, June 2, 2015. (WBZ-TV)

Authorities say Rahim and his nephew David Wright had discussed beheading anti-Islamic activist Pamela Geller and later talked about killing police officers.

At a news conference Thursday, Attorney Ronald Sullivan said claims that Rahim had been radicalized by ISIS came as a “complete shock” to his family.

Attorney Ronald Sullivan and Imam Ibrahim Rahim (WBZ-TV)

Attorney Ronald Sullivan and Imam Ibrahim Rahim (WBZ-TV)

Sullivan says the authorities who fatally shot Rahim didn’t have a warrant, and he’s calling for a thorough investigation.

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Rahim’s older brother is an imam and released a statement calling on Muslim communities to “remain calm” and to offer their prayers for Rahim.

Sullivan said Imam Ibrahim Rahim was mistaken when he initially claimed his younger brother was shot in the back. He says Ibrahim was relying on third-hand information, and “We now know we simply did not have all the facts.”

The family did not speak at the news conference. Sullivan says relatives are waiting for more evidence “in order to form a reasoned and informed opinion.” They went to the Suffolk County DA’s office to watch the surveillance video of the shooting Thursday night.

The family did not comment after the meeting, but one family member said, “Boston strong. God bless America.”

A burial is planned for Usaamah Rahim on Friday.

Suffolk County DA Dan Conley has pledged a “thorough, impartial, and unbiased investigation” and will release surveillance video of the shooting to the public after Rahim’s burial.

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