TWO massive bombs, both bigger than those used in the Boston Marathon attacks, were made with the intention of blowing up a Sydney hospital and the city offices of a leading Sydney eye surgeon, a court heard yesterday.

Two fully assembled bombs with detonators, packed with 60cm shrapnel pieces connected to a butane gas bottle, were found in a duffel bag under a home at Albion Park on the South Coast in April.

The devices were both set to go off at 1.48pm on April 6.

But, just days before the bombs were to detonate, the 42-year-old accused of making them fled Australia to Malta and they were never placed near their intended targets. The man's ex-wife, who was unaware of the alleged plot, found the bombs two days later and called police, Central Local Court was told.

The NSW bomb squad was then called in to examine the devices. Police were preparing to extradite the man from Malta but he was arrested at Sydney Airport on Thursday evening when he attempted to come back into the country.

He was charged with one count of manufacturing an explosive device with intent to injure. Police said the accused man had been being treated for an eye condition by the surgeon and believed a dye administered by the doctor had caused him an injury.