(CNN) Usaamah Rahim was a member of a very religious family and was devout himself, but two Muslim leaders said Wednesday there was no way he was a radical.
The men, from the Mosque for Praising Allah in Roxbury, Massachusetts, told reporters Wednesday that Rahim came from a good family. They said they were surprised he was accused of plotting to kill police officers.
Ismail Abdurrashid, an assistant imam, said the 26-year-old security guard was "a very pleasant young man."
He was a devout Muslim, Abdurrashid said. "He had a firm understanding of the religion," he said. "Observant, very much so."
Asked whether it's possible he could have been radicalized as authorities have alleged, he said, "No."
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On a Facebook page where Rahim posted as Abu Sufyaan, he liked in 2012 a page about the Islamic State of Iraq, or what is now ISIS.
In June 2013, he posted about his marriage, thanking two men for being witnesses. One of them is Dawud Sharif Abdul-Khaliq, an alias used by a man arrested Wednesday in the case. David Wright, 25, appeared in U.S. District Court in Boston on Wednesday to face a charge of obstructing a federal investigation.
A few months ago, Rahim changed the cover photo on the page to a dock extending over lake water with mountains in the distance. The saying on the photo: "Let not the opinions of man interfere with the directions given to you by God."
His profile photo is of a large gathering outside a mosque.
Abdurrashid described Rahim as calm, intelligent and youthful.
Authorities showed surveillance video of the incident during an unusual meeting Wednesday with religious and civil rights leaders in an attempt to allay community concerns about the shooting.
Abdurrashid said he didn't get a chance to see the video. Imam Abdullah Faaruuq, who did, said the recording was inconclusive.
Boston Police Commissioner William Evans said the surveillance video shows four or five officers approach the suspect without their weapons drawn. The officers backtrack as Rahim comes after them with a knife. They eventually draw their weapons and open fire.
Faaruuq said the distance from the camera to the incident made it difficult to determine whether Rahim had a knife.
The imam said he had known Rahim since he was 5. Rahim and his family would occasionally sit in the front of his mosque, but Rahim also visited other mosques.
Faaruuq praised Rahim's mother.
"She's educated, soft-spoken and highly intelligent. ... And she's a nurse and a mature woman," he said. "She is deeply saddened."
CNN affiliate WCVB reported the mother went to the state medical examiner's office Wednesday morning.
"We're grieving" were her only words, the Boston-based station reported.
The station also said Usaamah Rahim attended Brookline High School for three years, after returning from his freshman year in Saudi Arabia.
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Rahim graduated from Brookline High in 2007, according to a statement from the Public Schools of Brookline superintendent. He enrolled in Brookline in 2004 for 10th grade after spending a year at the Academic International School in Saudi Arabia, the statement said. Rahim also attended Baker School in Brookline for some time.
Rahim's guidance counselor and dean remember him as "a bright young man who benefited from the attention of his teachers and tutors in reaching graduation," the statement said. He had no major disciplinary infractions at Brookline High. After graduation, he went to college in Florida and, several years later, sent an email to his former dean and guidance counselor thanking them for helping him get through high school, according to the statement.
Rahim's brother, Mohammed, graduated from Brookline High in 2004.
Rahim lived with his mother, wife and two brothers.