By Tony Hanson

PHILADELPHIA (CBS) – A 10 year veteran of the Philadelphia Police Department and his brother have been charged with tax fraud, conspiracy, and the prosecution wants the defendant’s held pending trial based on concerns for the safety of witnesses.

Police officer Jose Tirado and his brother Victor allegedly used the names, birth dates and Social Security numbers of people, including children, to file false tax returns for underserved refunds totaling over a half million dollars; they alleged got over $400,000.

Prosecutor Ashley Lunkenheimer has requested pre-trial detention for both defendants.

“There is evidence he gave money to, offered to give money to, or offered otherwise to assist individuals subpoenaed to the federal grand jury or approached by law enforcement if they did not divulge his activities to law enforcement,” said Lunkenheimer about Jose Tirado.

His attorney says his client has not been charged with witness intimidation and he will plead not guilty to the charges that have been filed.

There’ll be a detention hearing next week.