(AP) — The Trump administration ratcheted up its feud with California on Wednesday as the Environmental Protection Agency issued a notice accusing San Francisco of violating the federal Clean Water Act.

Last month, President Donald Trump warned of a potential violation notice, saying the city was allowing needles and human waste to go through storm drains to the Pacific Ocean _ an allegation fervently denied by city officials.

The violation notice came in the form of a letter to Harlan Kelly, Jr., general manager of the city’s Public Utilities Commission.

It said the EPA had identified violations in the city and county wastewater treatment and sewer system, including lack of proper operation and maintenance that has allowed raw and partially-treated sewage to flow onto beaches into the ocean and sometimes into streets and homes.

The letter alleged that some discharges contained heavy metals and bacteria and said the city hasn’t kept up proper cleaning, inspection and repair schedules for the system nor properly reported or issued public warnings for sewage diversions.

It’s the latest salvo in a feud between the administration and Democrat-controlled California, which has filed more than 50 lawsuits opposing Trump initiatives on the environment, immigration and health care.

EPA Administrator Andrew Wheeler sent a letter to Gov. Gavin Newsom last week alleging waste left by the homeless in big cities such as San Francisco and Los Angeles was being improperly handled.

Mayor London Breed said the violation notice contains “mischaracterizations, inaccuracies and falsehoods” and the city’s sewer system is one of the most effective in the country.

“No debris flow out into the (San Francisco) Bay or the ocean,” Breed said in a statement, adding that San Francisco has a multibillion-dollar program to upgrade its sewage treatment system.

“The same Trump EPA that is dismantling environmental protections around the country is now making fraudulent claims about San Francisco’s combined sewer system,” state Sen. Scott Wiener, D-San Francisco, said in a statement. He called the notice “a fraudulent political attack on San Francisco by a collapsing administration desperate to rile up its base.”

The EPA notice contained a veiled warning that it retains the option of seeking fines and penalties through administrative, civil or criminal actions over the violations.

Wheeler’s letter to the governor last week didn’t lay out any specifics on possible disciplinary actions, although they could include withholding funds or revoking California’s authority to administer federal laws such as the Clean Water Act. The latter would seem highly unlikely, however, because EPA would have to assume the expense of running the programs itself.