SACRAMENTO (CBS SF) — California Governor Jerry Brown rejected a measure to open safe drug injection sites in San Francisco on Sunday.

The city of San Francisco and its mayor, London Breed, have been pushing to open the safe injection sites, with hopes that they would take drug users off of the streets and into clean facilities with access to counseling.

The program came about after countless complaints of used drug paraphernalia, human waste and trash in the San Francisco streets being linked to open drug use.

RELATED: San Francisco Officials Promote Safe Injection Program With Mock Facility

In August, the city opened a mock facility at Glide Memorial Church to demonstrate how a safe injection site would operate.

The bill, written by Assemblymember Susan Eggman (D-Stockton) and co-authored by Senator Scott Wiener (D-San Francisco), would have allowed San Francisco to open safe injection sites under a three-year pilot program.

“I want to reduce the stigma around these sites and show that they can be implemented in a clean, safe and effective way,” said Breed.

However, Brown’s veto may not stop San Francisco from becoming the first U.S. city to open a safe injection site. Breed said that the city will “continue to work” to move the effort for safe injection sites forward.

Breed is such an advocate for the program that she has said she doesn’t fear prosecution or jail time from federal authorities.

Brown said that supporting supervised drug use will “never work.”

“I’m disappointed that the Governor has vetoed this important public health bill. Safe injection sites save lives. If we are going to prevent overdoses and connect people to services and treatment that they badly need to stop using drugs in the first place, we need safe injection sites,” said Breed in a statement following the veto.

Governor Brown was hard at work on Sunday, signing and vetoing many bills into and away from California policy. Some major measures that Brown signed included the toughest net neutrality bill in the country and a bill requiring women to be on corporate boards.