California officials are declining to release nearly year-old findings into the safety of oilfield injection wells in the Los Angeles area.

Regulators say they carried out a "highest priority" probe into whether oilfield injection wells were polluting drinking-water aquifers in and around Los Angeles.

State officials say the draft report was completed last August. But they refused an Associated Press request at the time to make public the findings. They refused again on Thursday.

State oil and gas supervisor Steve Bohlen told the AP on Thursday that he expects the report would be released within weeks with policy changes recommended.

The Center for Biological Diversity called the information vital to the public health and urged the state to release it.