SAN FRANCISCO » The mayor of San Francisco said Tuesday that four police officers under investigation in the sending of racist and homophobic texts will be fired if the probe determines they sent the messages.

Mayor Edwin M. Lee called the messages heinous and despicable, and called for immediate disciplinary action against the officers.

The city’s Board of Supervisors said it will hold a hearing to look into bias in the city’s justice system and ask for input from the San Francisco Police Department, public defender’s office, district attorney’s office and Office of Citizen Complaints, which investigates complaints against police officers.

"When things of this nature surface, we have to look long and hard at what’s actually happening in the department," said board President London Breed.

The texts targeting blacks, Mexicans, Filipinos and gay men were discovered by federal authorities investigating former police Sgt. Ian Furminger, who was convicted of corruption and sentenced to 41 months in federal prison.

The names of the officers have not been released by police, but attorneys representing them have identified them as Michael Robison, 46; Noel Schwab, 49; Rain Daugherty, 40; and Michael Celis, 47.

Attorney Alison Berry Wilkinson said Daugherty is "appropriately ashamed by his impulsive and insensitive banter, and accepts full responsibility for the content of those text messages that he sent, which are by no means a reflection of his true character or his style of policing."

Robison and Celis also regret their involvement in the messages, said Anthony Brass, their lawyer.

"They are very clear that this is not acceptable banter," Brass said, "and they understand why the communities in San Francisco would take this very seriously and find it deeply offensive."

Brass also said Schwab is one of the officers under investigation. However, a lawyer he said represents Schwab was not immediately available for comment.

The officers have been reassigned and will have no interaction with the public during the investigation, a decision the association supports.

The messages were sent between Furminger and the officers in 2011 and 2012 and disclosed in court documents, authorities said.

"The content of these text messages displays a bias that is incompatible with the values of our city and incompatible with the ability to perform sworn duties as a police officer," Lee said. "If these statements are attributable to any San Francisco police officer, I join Police Chief Greg Suhr in seeking nothing less than termination."

The San Francisco Police Officers Association issued a statement saying the actions were not emblematic of individuals it represents.

"All these racist and homophobic text messages, if true, are disgraceful and humiliating to the community we serve," the statement said.

Authorities said the texts feature the repeated use of the phrase "white power" and references to burning crosses and the Ku Klux Klan.

District Attorney George Gascon said his office will review all cases going back 10 years that the officers were linked to either by writing a report, submitting evidence or testifying in court. He said there is no place for bigotry in San Francisco.

Furminger told KGO-TV, an ABC affiliate in San Francisco, that the messages were taken out of context and were banter among friends.

"Those texts are not a reflection of who I am. It’s a rebound reaction to a politically correct environment," he said.

Furminger said he grew up in the racially diverse East Bay, went to a mostly black high school and never had a racial complaint while as a police officer.