Three Irish nationals have been arrested after allegedly targeting elderly Sydney residents with a roofing scam.

Detectives hid in the house of a 72-year-old man who was allegedly charged $13,000 for the repairs that police say left holes in his roof.

When the four men returned to the house where the detectives were waiting, they ran off, leaving their car behind.

Police say the Bexley resident had received a flyer in his mailbox about the roof repairs.

A 20-year-old Irish national, headed for the UK, was arrested at Sydney Airport with three watches valued around $73,000 along with $8,000 cash.

He has been charged with aggravated break and enter and denied bail.

Later, a 22-year-old Irish national was arrested trying to board a flight to Qatar and charged with fraud.

The third man, a 20-year-old Irish national, was arrested at Melbourne’s Tullamarine airport.

Police are seeking his extradition from Victoria.

NSW Police Detective Chief Inspector Robert Allison tells Ray Hadley they don’t believe the fourth man has left the country.

“Hopefully we’ll be able to locate this person in the next few days.”

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