OAKLAND -- Alameda County officials said Wednesday they have no authority to stop immigration agents from detaining and deporting an Occupy Oakland protester who was arrested while meditating outside City Hall.

The District Attorney's office dropped misdemeanor charges against 36-year-old activist Pancho Ramos Stierle for loitering and refusing to disperse from Frank H. Ogawa Plaza as riot police were clearing out the Occupy encampment there on Monday.

But while the criminal charges were dropped on Wednesday afternoon, a federal immigration hold on Ramos Stierle remains in effect and friends fear he could be deported to Mexico.

"I don't have the authority to go against the federal government," said Alameda County Superior Court Commissioner Karen Rodrigue, speaking to dozens of Ramos Stierle's supporters who came to his arraignment in a downtown courthouse.

The peace activist was among those arrested as riot police cleared the Occupy encampment in a predawn raid Monday.

He had been meditating on the plaza for more than three hours as police officers surrounded the camp and most other protesters fled.

After he was booked in a county jail, a federal fingerprints database flagged him as a deportable immigrant from Mexico. Agents from U.S. Immigration and Customs Enforcement sent a note to jailers asking him to be held.

The activist's lawyers argued on Wednesday that the note -- called an immigration detainer -- is merely a request for local authorities to keep him detained, not a demand, and that the county has the ability to reject it.

"Our position is that they don't have to honor the hold. That's clear as day," said lawyer Francisco Ugarte. "The federal government has said the hold is a request."

The sheriff's department and district attorney's office disagreed.

"The sheriff's department is going to pay attention to what the feds tell them to do," said Deputy District Attorney Josefa James, speaking in the courtroom to one of Ramos Stierle's lawyers.

On the immigration hold, James said, "we don't have anything to do with it, but there's nothing we can do about it, either."

About 50 activists and friends formed a meditation circle outside the courtroom and shared stories about Ramos Stierle as they awaited his arraignment.

Equipped with notepads, pens, cellphones and laptops, they spent hours making phone calls and writing emails and handwritten letters to local authorities.

"We all have the responsibility to do the right thing, and we're asking (District Attorney) Nancy O'Malley to do the right thing in this instance," said his lawyer, Yolanda Huang.

O'Malley did not return a request for comment.

Although Ramos Stierle is now in the county's custody, not the city's, Huang said county and federal authorities should respect ordinances approved by the Oakland City Council, which declared the city a sanctuary for all immigrants -- first in 1986, and then again in 2007.

"He was arrested on city property," Huang said. "He was arrested by Oakland police officers. And he's been held in the city of Oakland."

However, that "City of Refuge" policy has not been enforced, especially since Alameda County and all other Bay Area counties joined the federal Secure Communities network last year. Fingerprints of everyone arrested by local police get automatically sent to a federal database, which flags arrestees who appear to be immigrants subject to deportation, either because they are in the country illegally or committed a crime.

Lawyers and immigration authorities have declined to discuss how Ramos Stierle was able to live in the U.S. and whether or not he had permission to be living here.

"We are not at liberty to disclose further details about Mr. Stierle's immigration history," said U.S. Immigration and Customs Enforcement spokeswoman Virginia Kice, citing privacy restrictions. The agency has also not said if it intends to take custody of Ramos Stierle, but it did ask the county to keep him detained until agents decide if they wish to pick him up.

Lawyers said the immigration agency has 48 hours after the arraignment, which was late on Wednesday afternoon, to make that determination.

Friends said Ramos Stierle was from Mexico City and had studied at UC Berkeley on a student visa.

He dropped out of a graduate astrophysics program at the university in 2008 and became a full-time activist, they said.

A resident of Oakland's Fruitvale district, he gathered fruits from neighborhood trees and leftover organic produce from farmers markets and distributed the food for free to residents who needed it. He was involved in a range of causes, from immigrant rights to environmentalism, and had protested the city's gang injunctions. Much like a Buddhist monk, he lived off a "gift economy," supported by friends he inspired through his activism and secular spirituality.

"He only rides bikes," said friend Miriam Dowd, visiting the courtroom Wednesday. "He calls gasoline 'dinosaur juice.'"

Inspired by Gandhi, Ramos Stierle spent each Monday in silence, communicating only through writing. He was following that practice when Oakland police officers approached him after 6 a.m. Monday and arrested him.

When they asked him questions, he answered on a notepad. He maintained the vow of silence all day in the county jail, but cracked a smile every once in a while, said cellmate Paul Bloom of San Francisco.

"He was doing nothing but being a peaceful presence. That was our intention," said Adelaja Simon, 24, who was meditating with Ramos Stierle and another activist when the three of them were arrested. Simon, Bloom and more than 30 other arrested protesters were released later that day, but Ramos Stierle was kept in the county's custody because of the immigration hold.

Simon said Ramos Stierle was conscious of his actions and he did not feel worried about what would happen to his friend.

"He's calm and he's present, and wherever he lands, he'll still stand for love and he'll keep doing good work for the community," Simon said.

Staff writer Robert Salonga contributed to this story.