'Shocking': Men were strangers before one was allegedly fatally thrown over balcony

A man is in police custody facing a murder charge after he allegedly threw a 74-year-old man from a first-floor balcony in an "unprovoked attack" in Brisbane's south.

Michael Thomas Chesworth was at his Yeronga home with his wife when he heard a knock at the door about 1.40pm yesterday.

Police have alleged a stranger, 49-year-old Raymond John Binge, was at the door.

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Detective Superintendent Andrew Massingham alleged Binge had been going aggressively "door to door" seeking certain items from people.

One line of inquiry is that he was seeking cigarettes but officers are still investigating.

Police said that a disagreement then occurred between Chesworth and Binge.

"During the course of that disagreement, we allege the 49-year-old man physically picked up the deceased and threw him over the railing," Massingham said.

Officers say Chesworth fell around 3.5 metres and suffered critical head injuries.

He was taken to hospital in a critical condition but couldn't be saved.

"His partner is devastated, she is with us at the moment," Massingham said.

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Binge was allegedly found inside a nearby unit by officers.

Police said the two men were not known to each other and that Binge was an associate of someone who lives at the unit block.

Neighbours have been left shocked by the incident.

"He was just in recession for nine months treatment of lung cancer," one neighbour said.

"Shocking, shocking."

"This is horrendously tragic and confronting," Massingham said.

Binge didn't appear in court when his matter was heard today.

His case has been adjourned ahead of a bail application scheduled for next month.