Washington, June 19 (IANS) The US needs to make renewed attempts to help the jailed Pakistani doctor who led the US to Osama bin Laden, a Congressman has said.

Republican Dana Rohrabacher from California has made Shakil Afridi's case a personal cause, but fears the issue has fallen off the political radar, the Daily Mail reported.

He said without US intervention, the man credited with helping track down Osama bin Laden would be left to "suffer in a dungeon".

"If we let that person just hang on a limb and forget him, now that he's put himself in danger for us -- well shame on us. I am very concerned that the United States will shame itself by letting Dr. Afridi sit there and suffer in a dungeon, and be tortured," Rohrabacher said.

"It doesn't appear that other people are taking this case seriously. I don't see any movement," he said.

Afridi helped the CIA by running a fake vaccination programme that allowed him to collect the DNA of bin Laden's children from the family compound in Abbottabad.

Sample analysis confirmed the terror chief was probably there and triggered the deadly mission by US Navy SEALS in May last year.

Pakistani officials felt the operation was a violation of the country's sovereignty.

After the raid, Afridi was arrested for conspiring against Pakistan, and last month jailed for 33 years.

Rohrabacher told Fox News he was "frantically" trying to keep a focus on the doctor's fate, and said officials were neglecting the case which reflects badly on the US.

Afridi's brother Jamil told Fox News that the doctor had suffered torture while in custody ahead of his sentencing and previously appealed to the US embassy in Islamabad for help to fight his legal case.

The US has insisted there was no basis to imprison Afridi on treason charges. Secretary of state Hillary Clinton said in May that she regretted "both the fact that he was convicted and the severity of his sentence".

State Department spokesman Mark Toner said they were still focused on the case, and "continue to urge Pakistan to consider his appeal in a manner that is expeditious, transparent and consistent with due process".

In May, outraged at Afridi's conviction, US Senate panels voted to cut aid to Islamabad by $33 million -- one million for every year of the physician's 33-year sentence.