SAN DIEGO - A California woman has been charged with conspiring to provide money and people to a Somali terrorist group to help carry out killings in the African nation, according to a federal indictment unsealed Monday.

Nima Ali Yusuf, a 24-year-old permanent resident of the US, conspired in Southern California and elsewhere to aid al-Shabab, an al-Qaida-linked militia trying to create an Islamic state in Somalia, the indictment states.

Federal prosecutors did not provide further details on the allegations.

Since 2007, roughly 20 men have left Minnesota to fight with al-Shabab. Authorities said one became the first known US citizen to do a suicide bombing when he launched an attack in Somalia.

The FBI said he might have been "radicalized" in Minneapolis.

It wasn't immediately clear from the indictment whether Yusuf was connected to those men.

Yusuf was the fourth person charged in the past month in San Diego with helping al-Shabab. The others were accused of helping raise money and route funds to the radical Islamist group.

The indictments come as the US government cracks down on those suspected of helping al-Shabab.

Earlier this month, the US banned all cargo from Somalia in response to a plot by terrorists in Yemen who hid two powerful bombs inside printers shipped to Chicago.

A senior administration official, who spoke on condition of anonymity because he was not authorized to speak publicly, said there was no intelligence linking Somalia to a similar plot, but he said al-Shabab has said it intends to attack the US, just as al-Qaida in the Arabian Peninsula has stated and tried to do.

Yusuf was arrested Friday in San Diego and appeared in federal court Monday, federal prosecutor Sabrina Feve said.

Yusuf was charged in the indictment with conspiracy to provide material support to terrorists; conspiracy to provide material support to a foreign terrorist organization; and making a false statement to an FBI agent and Customs and Border Protection officer when she allegedly denied sending money to anyone in Somalia in the past year.

Yusuf was being held without bail pending a November 18 hearing. The federal defenders office said they did not have an attorney listed for her yet.

Bashir Hassan of HARO, a San Diego-based African relief organization, said Yusuf used to volunteer in the office, answering phones and making calls. The group collects mostly clothes to send to the poor in Somalia.

He said he was not aware of her involvement in helping al-Shabab.

"I don't know what to say," he said. "When the government makes allegations, I think it's the government's job to bring evidence. But I didn't see anything, as far as that happening."

During the past two years, Minneapolis has been the center of a federal investigation into al-Shabab recruitment.

E.K. Wilson, a counterterrorism supervisor with the FBI in Minneapolis, said his office is coordinating closely with colleagues in San Diego, but added he could not comment on whether Yusuf is directly connected to the Minnesota men who went overseas to fight.

He referred questions to the FBI or US Attorney's Office in San Diego, where officials declined to comment further.

A total of 19 people have been charged in the case in Minnesota with a variety of counts ranging from providing material support to terrorists to perjury. Three men who went to Somalia and returned to the US after spending time in al-Shabab training camps have pleaded guilty to material support charges in federal court in Minnesota and are awaiting sentencing.

Most of the other men who went to fight in Somalia are still at large. Some are dead or feared dead.

The defendants include two women accused of being part of a pipeline that routed money and fighters from the US to al-Shabab by going door to door in Rochester, Minnesota, Minneapolis and other cities in the US and Canada to fraudulently raise money for al-Shabab's operations in Somalia.

They falsely claimed the donations would go to the needy and allegedly held teleconferences to make direct appeals for support for al-Shabab, according to the indictment.