The Somali Community of Victoria says it is shocked and deeply saddened by Friday's deadly Bourke Street attack.
Investigations continue into the incident.
Somali-born, Hassan Khalif Shire Ali - known to authorities for his radical views - set fire to a car and stabbed three people, before being shot by an officer.
A 74-year-old man died at the scene and two others have been hospitalised.
Somali Community spokesman Sharmarke Farah says his group condemns the abhorrent and despicable act.
"(We stand with the victims of this incident and send our deepest and sincere condolence to their families and friends. We commend and thank Victoria Police for their swift, measured and professional response and in bringing the situation promptly under control."
Mr Farah says anyone with information about the attack should speak to police.
"We urge anyone with information to come forward. the overwhelming majority of African Australians in Victoria are law abiding and condemn any acts that threaten our peaceful, vibrant and multicultural state of Victoria that we love so dearly."
The Federation of African Communities Council of Australia has called the Bourke Street attack sad and unfortunate.
National Vice-President, Edward D. Solo says his heart goes out to all those affected.
He says people need to have courage to face these situations and learn from them so they won't be repeated.
"We are devastated by this incident and we want all of us as a people - both African and other Australians to hold together in a situation of this nature. We don't encourage anything that is harmful to anybody, any human being for that matter and therefore anything that is a threat to lives and property is something that we don't support."
Both sides of federal politics condemned Islamic extremism following the deadly attack.
Prime Minister Scott Morrison says he has to speak out - over what he's called, the radical and dangerous ideology of extremist Islam.
I've got to address the real issue. I've got to call it out. Radical, violent, extremist Islam that opposes our very way of life."
Opposition leader Bill Shorten says authorities must be ruthless and relentless against people who commit evil acts.
"Ever since 1014, the security threat in Australia has been upgraded. I've worked with prime ministers Abbott and Turnbull and now Morrison and we've all shared the same desire to do everything we can to oppose the violent Islamic extremist message which has become prevalent."
The Refugee Action Collective has urged federal and state politicians not to use the Bourke Street incident to drum up racism.
Collective spokesman Chris Breen says this tragedy is not a reason to run fear-mongering campaign agendas.
He says innocent and vulnerable people - who've come to Australia as refugees - can feel anxious.
