SYDNEY (AFP) - An Australian man charged over a bomb plot was seeking revenge against a doctor using devices larger than those used in the Boston Marathon blast, reports said on Saturday.

The 42-year-old was arrested at Sydney airport on Thursday and charged with manufacturing an explosive device with intent to injure in connection with the plot, uncovered in April, police said in a statement.

"A man has been charged after an improvised explosive device was allegedly found at a home in Albion Park earlier in the year," police said.

He appeared before a magistrate in Sydney on Friday and was refused bail.

Prosecutors told the court he had assembled two shrapnel-packed butane gas bombs to detonate in one of the city's hospitals and offices of his eye surgeon, according to media reports.

The Daily Telegraph said the court had heard that the devices were both bigger than those used in April's Boston Marathon blasts, which killed three people and wounded more than 250.

The man, whose identity has been suppressed along with details of his alleged targets, had planned to detonate the bombs in the two locations over what he believed to be an injury caused by dye administered to him during testing for a genetic eye condition, The Australian newspaper said.

He allegedly intended to set off the blasts in April but fled to Malta before going through with the plot, leaving his ex-wife to find the devices hidden underneath their house, according to The Australian. She called the police, who sent in the bomb squad.

Moves were under way to have the man extradited from Malta when he attempted to re-enter Australia on Thursday and he was arrested at the airport, reports said.