SYDNEY — An illegal gun supply network from Nashville in the United States to Sydney, where there has been a spate of drive-by shootings, has been shut down, police said on Friday.

In a joint operation by Australian and US law enforcement officers, three men were arrested in Nashville on Wednesday with police alleging they bought firearms in Tennessee and shipped them to Australia.

"For several months, agencies have been investigating the illegal importation of firearms to Sydney from Nashville," New South Wales state police said in a statement.

"The agencies identified 20 firearms purchased in Nashville that are believed to have been illegally sent to Sydney."

Parts of Sydney's west and southwest have been plagued by drive-by shootings this year, most recently on Thursday evening when a man was shot in the thigh.

Many of the incidents involve gangs fighting over drugs and territory.

Earlier this year, a criminal syndicate smuggling black-market handguns into Sydney from Germany was smashed.